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2606.12409 2026-06-11 cond-mat.quant-gas cond-mat.str-el physics.atom-ph quant-ph 新提交

A Pfaffian quantum Hall state of ultracold bosons

超冷玻色子的Pfaffian量子霍尔态

Joyce Kwan, Perrin Segura, Yanfei Li, Tizian Blatz, Annie Zhi, Brice Bakkali-Hassani, Annabelle Bohrdt, Martin Greiter, Fabian Grusdt, Markus Greiner

AI总结 通过Floquet合成磁场和贝叶斯优化绝热协议,在光晶格中制备超冷铷原子的三体玻色子Pfaffian态,观测到配对关联和短程三体抑制,为研究非阿贝尔任意子编织奠定基础。

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9+11 pages, 5+9 figures
AI中文摘要

分数量子霍尔态是拓扑物理学的基石,承载具有奇异统计特性的分数电荷准粒子,有望实现拓扑保护的量子信息处理。其中,Moore和Read引入的Pfaffian态实现了p波配对结构,支持具有非阿贝尔交换统计的激发。尽管在电子系统中进行了广泛研究,但其配对结构的直接探测仍然有限。在这里,我们在受Floquet工程合成磁场作用的光晶格中,利用超冷$^{87}\mathrm{Rb}$原子实现了三体玻色子Pfaffian态。通过贝叶斯优化的绝热协议,我们制备了一个展现Pfaffian配对关联的态。多点密度关联的位点分辨测量揭示了短程三体重合的显著抑制,反映了潜在的配对结构。我们进一步通过霍尔漂移测量探测了该态的输运响应。我们的结果建立了一种自下而上的工程非阿贝尔拓扑序的方法,并为未来在合成物质中探索任意子编织奠定了基础。

英文摘要

Fractional quantum Hall states are a cornerstone of topological physics, hosting fractionally charged quasiparticles with exotic statistics that promise to enable topologically protected quantum information processing. Among these, the Pfaffian state introduced by Moore and Read implements a p-wave pairing structure that supports excitations with non-Abelian exchange statistics. Despite extensive study in electronic systems, direct access to its pairing structure has remained limited. Here we realize a three-particle bosonic Pfaffian state of ultracold $^{87}\mathrm{Rb}$ atoms in an optical lattice subject to a Floquet-engineered synthetic magnetic field. Using a Bayesian-optimized adiabatic protocol, we prepare a state exhibiting Pfaffian pairing correlations. Site-resolved measurements of multi-point density correlations reveal a pronounced suppression of short-range three-body coincidences, reflecting the underlying pairing structure. We further probe the state's transport response through Hall drift measurements. Our results establish a bottom-up approach to engineering non-Abelian topological order and lay the groundwork for future explorations of anyonic braiding in synthetic matter.

2606.12408 2026-06-11 hep-ph astro-ph.CO 新提交

When direct detection constrains reheating temperature: freeze-in with stronger couplings and inflaton-seeded freeze-in

当直接探测约束再加热温度:具有更强耦合的冻结产生和暴胀子播种的冻结产生

Xavier Bertou, Olivier Deligny, Mathieu Gross, Yann Mambrini, Issam-Eddine Mellouki

AI总结 本文分析DAMIC-M和PandaX实验对更强耦合或非热源(如暴胀子衰变)的冻结产生模型中再加热温度的约束,并找到在避免电子散射截面实验限制下正确重现暗物质遗迹密度的可行方案。

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AI中文摘要

DAMIC-M和PandaX合作组的最新结果已经排除了在标准模型扩展中引入额外超轻$U(1)_{\rm X}$规范玻色子的情况下,质量范围$3~\mathrm{MeV} \lesssim m_\chi \lesssim 1~\mathrm{GeV}$内的标准冻结产生暗物质。在这项工作中,我们分析了DAMIC-M和PandaX结果对更强耦合冻结产生模型中再加热温度的约束,或者当非热源(如暴胀子衰变)发挥作用时的情况。我们识别了可行的情景,在这些情景中,暗物质遗迹丰度被正确重现,同时规避了当前对电子散射截面$\overline{\sigma}_\mathrm{e}$的实验限制。特别地,我们表明,对于低于电弱尺度的再加热温度,玻尔兹曼抑制的产生可以通过更强的耦合来补偿,使冻结产生情景处于当前实验可及范围内。最后,我们研究了一种混合情景,其中暴胀子衰变的一个小分支比播种了非零的初始暗物质丰度。我们表明,这种贡献可以显著改变广泛参数空间中的冻结产生预测,为探测极弱相互作用提供了额外途径。

英文摘要

Recent results from the DAMIC-M and PandaX collaborations have excluded the standard freeze-in production of dark matter for masses in the range $3~\mathrm{MeV} \lesssim m_\chi \lesssim 1~\mathrm{GeV}$ in the context of extensions of the Standard Model featuring an additional ultra-light $U(1)_{\rm X}$ gauge boson. In this work, we analyze the constraints induced by DAMIC-M and PandaX results on the reheating temperature in freeze-in models at stronger coupling, or when a non-thermal source (such as inflaton decay) comes into play. We identify viable scenarios in which the DM relic abundance is correctly reproduced while evading current experimental bounds on the electron-scattering cross section, $\overline{\sigma}_\mathrm{e}$. In particular, we show that for reheating temperatures below the electroweak scale, Boltzmann suppressed production can be compensated by stronger couplings, bringing freeze-in scenarios within present experimental reach. Finally, we study a hybrid scenario in which a small branching ratio of inflaton decay seeds a nonzero initial dark-matter abundance. We show that such contributions can significantly modify freeze-in predictions across broad regions of parameter space, offering an additional pathway for probing extremely feeble interactions.

2606.12405 2026-06-11 astro-ph.CO 新提交

Bounding the Effect of HOD Assumptions on Small-Scale Clustering Constraints

HOD假设对小尺度成团约束的影响界限

Nick Magnelli, Zachery Brown, Lado Samushia

AI总结 利用AbacusSummit模拟的LRG星系目录,量化HOD模型假设对小尺度成团约束的影响,发现保守与乐观HOD先验下排除的宇宙学比例差异显著(25% vs 81%),表明强约束需信息性星系-暗晕先验。

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22 pages, 15 figures
AI中文摘要

小尺度星系成团预计包含大量宇宙学信息,但这些信息在多大程度上独立于假定的星系-暗晕联系来约束基于暗晕的宇宙学仍不清楚。我们使用从{\tt \textsc{AbacusSummit}}套件中81个宇宙学构建的类LRG模拟星系目录量化这种依赖性。我们分析了从$5$到$80$ Mpc/$h$尺度上的两点相关函数多极矩,并比较了标准五参数HOD模型的两种极限处理:\enquote{下限}和\enquote{上限}。在保守的下限情形中,我们仅施加宽泛的初始HOD边界,并对HOD参数进行轮廓化以确定可用的最小约束能力;我们通过{\tt HODmin}实现这一点,这是一个为在HOD空间中最小化$\chi^2$而编写的两阶段全局优化算法。在乐观的上限情形中,我们假设HOD参数完全已知。我们发现,在相同的建模假设下,与相同的Planck $\Lambda$CDM模拟数据向量比较时,下限和上限之间存在显著差异:对于下限,测试的离散{\tt \textsc{AbacusSummit}}宇宙学中有$25\\%$在$3\sigma$水平被排除,而对于上限,约$81\\%$被排除。许多宇宙学在下限中与数据吻合良好,但在上限中却被$\chi^2$多个数量级排除。因此,我们观察到小尺度成团约束的强度在很大程度上取决于假设的HOD先验信息量。我们比较了这种效应对各种选择的敏感性,如尺度截断、角度截断、多极矩包含、模拟相位和模拟HOD模型。我们宽泛的下限-上限区间表明,信息性星系-暗晕先验对于提取强小尺度成团约束是必要的。

英文摘要

Small-scale galaxy clustering is expected to contain substantial cosmological information, but the extent to which this information constrains halo-based cosmologies independent of an assumed galaxy--halo connection remains unclear. We quantify this dependence using LRG-like mock galaxy catalogs built from 81 cosmologies in the {\tt \textsc{AbacusSummit}} suite. We analyze two-point correlation function multipoles on scales ranging from $5$--$80$ Mpc/$h$ and compare two limiting treatments, the \enquote{floor} and \enquote{ceiling}, of the standard five-parameter HOD model. In the conservative floor case, we impose only broad initial HOD bounds and profile over HOD parameters to determine the minimum constraining power available; we accomplish this with {\tt HODmin}, a two-stage global optimization algorithm written for minimizing $\chi^2$ in HOD space. In the optimistic ceiling case, we assume the HOD parameters are known exactly. We find a significant difference between the floor and ceiling when comparing against the same Planck $\Lambda$CDM mock data vector with identical modeling assumptions: for the floor, $25\%$ of the discrete {\tt \textsc{AbacusSummit}} cosmologies tested are excluded at $3\sigma$, whereas for the ceiling, $\sim81\%$ are excluded. Many cosmologies agree well with data in the floor, and yet in the ceiling are excluded by multiple orders of magnitude in $\chi^2$. We therefore observe the strength of small-scale clustering constraints depends heavily on the amount of prior HOD information assumed. We compare the sensitivity of this effect to various choices like scale cut, angle cut, multipole inclusion, mock phase, and mock HOD model. Our wide floor--ceiling bracket indicates that informative galaxy--halo priors are necessary for extracting strong small-scale clustering constraints.

2606.12404 2026-06-11 hep-ph astro-ph.HE quant-ph 新提交

Collective neutrino oscillations: Many-body non-forward effects and non-classicality

集体中微子振荡:多体非前向效应与非经典性

Julien Froustey, Ermal Rrapaj, Yuhao Liu, Gushu Li, Costin Iancu, Vincenzo Cirigliano

AI总结 研究密集天体环境中中微子演化的多体非前向散射效应,通过量子动力学与完整多体哈密顿量对比,揭示时间尺度和渐近行为差异,并分析量子计算资源需求。

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25 pages, 12 figures
AI中文摘要

密集天体环境中中微子演化通常用量子动力学框架描述(忽略多体关联积累),或通过简化多体计算(允许显著纠缠发展)。本文在简单中微子气体构型中比较这两种方法,特别强调非前向散射过程的作用。这些效应通过动力学描述中的碰撞项或考虑完整的中微子-中微子多体哈密顿量纳入。我们突出两种描述在特征时间尺度和渐近行为上的差异。受量子计算天然适合多体计算的启发,我们进一步研究中微子演化的非经典性,讨论Trotter误差缩放,以及构建量子电路在纠缠门和非Clifford门方面的相关成本。我们发现,中微子多体演化所需的资源在典型高能物理问题中处于低端,而在量子化学问题中处于中高端。对于完整哈密顿量,资源需求相对于截断版本增加。我们强调高效费米子到量子比特编码的重要性,这对于减少此类模拟所需的大量计算资源至关重要。

英文摘要

Neutrino evolution in dense astrophysical environments is typically described either within a quantum kinetic framework, which neglects the build-up of multi-body correlations, or through simplified many-body calculations that allow significant entanglement to develop. In this work, we compare these two approaches in a simple neutrino-gas configuration, with particular emphasis on the role of non-forward scattering processes. These effects are incorporated either through a collision term in the kinetic description, or by considering the full neutrino-neutrino many-body Hamiltonian. We highlight differences between the two descriptions in both their characteristic timescales and asymptotic behavior. Motivated by the natural suitability of quantum computing for many-body calculations, we further investigate the non-classicality of neutrino evolution, discussing Trotter error scaling, along with the associated costs of constructing quantum circuits in terms of entangling gates and non-Clifford gates. We find that the resources needed for neutrino many-body evolution are on the low end of typical high-energy physics problems and on the mid to high end with respect to quantum chemistry problems. For the full Hamiltonian, resource requirements increase relative to the truncated version. We emphasize the importance of efficient fermion-to-qubit encodings, which are essential for reducing the substantial computational resources required for such simulations.

2606.12401 2026-06-11 astro-ph.EP 新提交

The carbon isotope ratio of β Pic b with high-resolution spectroscopy

利用高分辨率光谱测量β Pic b的碳同位素比

D. González Picos, I.A.G. Snellen, R. Landman, S. de Regt, N. Grasser, J. L. Birkby, T. Stolker, I. Koutalios, M.A. Kenworthy

AI总结 通过CRIRES+高分辨率光谱测量年轻超级木星β Pic b的$^{12}C/^{13}C$比值为$58^{+18}_{-15}$,与当前星际介质一致,低于太阳值,并约束了大气参数和云层性质。

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Accepted to A&A
AI中文摘要

同位素比值追踪行星的形成和演化,并将其大气与原生原行星盘的化学性质联系起来。我们利用甚大望远镜(VLT)上CRIRES+的K波段光谱($\mathcal{R} \approx 100{,}000$)在11个夜晚测量了年轻超级木星$\beta$ Pic b大气中的$^{12}\mathrm{C}/^{13}\mathrm{C} = 58^{+18}_{-15}$。我们探测到$^{12}\mathrm{CO}$和$^{13}\mathrm{CO}$,并通过贝叶斯反演与近红外测光联合拟合约束了$^{12}\mathrm{C}/^{13}\mathrm{C}$。推断的$^{12}\mathrm{C}/^{13}\mathrm{C}$与当前星际介质(ISM)一致,低于太阳值,并与其他年轻超级木星的测量结果相当。我们还反演得到$T_{\rm eff} = 1629^{+30}_{-28}\\,\mathrm{K}$,近太阳至略超太阳的金属丰度([M/H]$ = 0.20^{+0.16}_{-0.12}$),类太阳的碳氧比(C/O$ = 0.52 \pm 0.03$),以及厚云的初步证据。我们独立分析每个夜晚,并合并信噪比(S/N)最高的六个历元的结果,将夜与夜之间的散射传播到最终不确定度中。这为位于CO雪线内的直接成像行星提供了一个同位素基准。

英文摘要

Isotopic ratios trace the formation and evolution of planets and link their atmospheres to the chemistry of their natal protoplanetary discs. We measure $^{12}\mathrm{C}/^{13}\mathrm{C} = 58^{+18}_{-15}$ in the atmosphere of the young super-Jupiter $\beta$ Pic b from 11 nights of CRIRES+ K-band spectroscopy ($\mathcal{R} \approx 100{,}000$) at the Very Large Telescope (VLT). We detect both $^{12}\mathrm{CO}$ and $^{13}\mathrm{CO}$ and constrain $^{12}\mathrm{C}/^{13}\mathrm{C}$ with a Bayesian retrieval jointly fitted with near-infrared photometry. The inferred $^{12}\mathrm{C}/^{13}\mathrm{C}$ is consistent with the present-day interstellar medium (ISM), is below the solar value, and is comparable to measurements in other young super-Jupiters. We also retrieve $T_{\rm eff} = 1629^{+30}_{-28}\,\mathrm{K}$, near-solar to mildly super-solar metallicity ([M/H]$ = 0.20^{+0.16}_{-0.12}$), a solar-like carbon-to-oxygen ratio (C/O$ = 0.52 \pm 0.03$), and tentative evidence for thick clouds. We analyse each night independently and combine the results of the six epochs with the highest signal-to-noise ratio (S/N), propagating night-to-night scatter into the final uncertainties. This provides an isotopic benchmark for a directly imaged planet interior to the CO snow line.

2606.12399 2026-06-11 physics.soc-ph 新提交

Revealing Peri-Urban Dislocation through Percolation Analysis

通过渗流分析揭示城郊错位

Dr Melissa Barrientos-Trinanes, Professor Stephen Marshall, Professor Elsa Arcaute

AI总结 提出城郊错位作为结构性条件,利用街道网络渗流分析揭示城市核心与外围的层级错位,并通过智利瓦尔迪维亚和美国波士顿案例展示两种不同表现。

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17 pages, 5 figures
AI中文摘要

本文引入城郊错位作为一种结构性条件,通过捕捉内城与外围区域之间的层级错位,补充了现有的蔓延度量指标。传统度量强调密度、土地利用混合度或碎片化,而城郊错位反映了城市系统核心-外围关系功能组织中更深层次的分歧。我们利用街道网络的渗流分析来操作化这一概念,通过聚类图和树状图揭示层级模式,提供城市元素之间的关系结构。两个案例研究——智利瓦尔迪维亚和美国波士顿——展示了对比鲜明的表现:瓦尔迪维亚的结构性逆转,其中同质化的居住外围主导了层级聚类过程;以及波士顿的城郊空洞,尽管大都市整合,孤立的细分地块仍然存在。这些发现将城郊错位定位为一种与蔓延相关但区别于基于密度或外围性度量的结构维度;它可能独立发生,或代表蔓延先前未被识别的结构特征。在方法论上,我们应用成熟的渗流技术来揭示这一先前未被阐述的结构现象,从而能够检测城市系统内的层级错位。在概念上,我们引入城郊错位作为城市结构的一个新维度,通过复杂性视角帮助阐明关于蔓延和城郊化的辩论,并实现跨不同城市背景的核心-外围诊断。

英文摘要

This paper introduces peri urban dislocation as a structural condition that complements existing sprawl metrics by capturing hierarchical misalignments between inner city and peripheral areas. Whereas conventional measures emphasise density, land-use mix, or fragmentation, peri-urban dislocation reflects deeper divergences in the core periphery relational functional organisation of urban systems. We operationalise this concept using percolation analysis of street networks, revealing hierarchical patterns via clustering maps and dendrograms, providing a relational structure between urban elements. Two case studies, Valdivia, Chile, and Boston, USA, demonstrate contrasting manifestations: a structural reversal in Valdivia, where a homogeneous residential periphery dominates the hierarchical clustering process, and peri-urban voids in Boston, where isolated parcellations persist despite metropolitan consolidation. These findings position peri-urban dislocation as a structural dimension linked to sprawl yet distinct from metrics based on density or peripherality; one that may occur independently or represent a previously unidentified structural signature of sprawl. Methodologically, we apply established percolation techniques to expose this previously unarticulated structural phenomenon, enabling the detection of hierarchical misalignments within urban systems. Conceptually, we introduce peri urban dislocation as a new dimension of urban structure, helping articulate debates on sprawl and peri urbanisation through a complexity informed lens and enabling core periphery diagnostics across diverse urban contexts.

2606.12398 2026-06-11 physics.optics cond-mat.mtrl-sci 新提交

Quantifying the Distribution of Biexciton Emission Efficiencies in Colloidal Quantum Shells

胶体量子壳中双激子发射效率分布的量化

Tjom Arens, Dulanjan Harankahage, Divesh Nazar, Mikhail Zamkov, Freddy T. Rabouw

AI总结 本文提出一种串扰抑制的SPAD阵列光子关联方法,高通量量化超过1000个胶体量子壳的多光子发射,发现双激子发射效率呈近高斯分布,平均值为0.55,估计内在标准差为0.12。

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AI中文摘要

多光子发射效率是量子光源的重要特性。高亮度多光子发射适用于高功率照明和激光,而其完全抑制则是高纯度单光子产生所必需的。在胶体量子发射器中,多光子发射在不同粒子间可能存在显著差异。传统的逐粒子方法难以解决这种异质性。本文介绍了一种串扰抑制的SPAD阵列光子关联方法,用于高通量量化超过1000个胶体量子壳的多光子发射。通过将同一样品的两个图像投影到探测器阵列的远距离区域,我们避免了探测器像素间的短程串扰。时间门控抑制了暗计数符合,并区分了单个发射体与团簇。将该方法应用于量子壳,揭示了双激子发射效率的近高斯分布,平均值为0.55,估计内在标准差为0.12。双激子效率与粒子亮度的批次内相关性与俄歇猝灭的体积标度一致。这些结果确立了SPAD阵列光子关联作为解决纳米粒子集合中多光子异质性的可扩展途径。

英文摘要

The efficiency of multi-photon emission is an important characteristic of quantum light sources. Bright multi-photon emission is desirable for high-power lighting and lasers, while its complete suppression is required for high-purity single-photon generation. In colloidal quantum emitters, multi-photon emission can vary significantly between individual particles. Resolving this heterogeneity remains challenging with conventional particle-by-particle approaches. Here, we introduce a crosstalk-suppressed SPAD-array photon-correlation approach for high-throughput quantification of multi-photon emission from more than 1000 colloidal quantum shells. By projecting two images of the same sample onto distant regions of the detector array, we avoid short-range crosstalk between detector pixels. Time gating suppresses dark-count coincidences and distinguishes individual emitters from clusters. Applying this method to quantum shells reveals a near-Gaussian distribution of biexciton emission efficiencies, with a mean of 0.55 and an estimated intrinsic standard deviation of 0.12. Intra-batch correlations between the biexciton efficiency and the particle brightness are consistent with the volume scaling of Auger quenching. These results establish SPAD-array photon correlation as a scalable route to resolve multi-photon heterogeneities in nanoparticle ensembles.

2606.12394 2026-06-11 quant-ph 新提交

Scaling-optimal purification of noisy qubit unitary channels

噪声量子比特酉通道的缩放最优纯化

Ryotaro Niwa, Satoshi Yoshida, Koki Ono, Takeru Utsumi, Zhaoyi Li, Yuxiang Yang, Ryuji Takagi, Mio Murao

AI总结 针对带噪声的量子比特酉通道,提出基于纠缠辅助量子纠错码的U(2)-协变并行协议,实现噪声强度O(1/n)抑制,并证明在低噪声区域渐近最优。

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6+9 pages, 2 figures
AI中文摘要

我们考虑纯化噪声量子比特酉通道的问题。给定应用未知量子比特酉通道后跟随去极化噪声的能力,我们旨在构建一个超通道,将噪声酉纯化回原始未知酉。我们首先提供数值证据,表明当通道使用次数有限时,顺序策略可以严格优于并行策略,突出了与状态纯化的根本区别。然后,我们基于一种新颖的纠缠辅助量子纠错码,提供了一个具体的$\mathrm{U}(2)$-协变并行协议,该协议将一阶噪声强度抑制为$O(1/n)$,其中$n$为通道使用次数,并证明在低噪声区域,即使允许顺序策略,这种缩放也是渐近最优的。

英文摘要

We consider the problem of purifying noisy qubit unitary channels. Given the ability to apply an unknown qubit unitary channel followed by depolarizing noise, we aim to construct a superchannel that purifies the noisy unitary back to the original unknown unitary. We first provide numerical evidence that sequential strategies can strictly outperform parallel strategies when the number of channel uses is finite, highlighting the fundamental distinction from state purification. We then provide a concrete $\mathrm{U}(2)$-covariant parallel protocol based on a novel entanglement-assisted quantum error-correcting code that suppresses the first-order noise strength as $O(1/n)$ with $n$ channel uses and show this scaling is asymptotically optimal in the low-noise regime, even when sequential strategies are allowed.

2606.12393 2026-06-11 hep-ph hep-th physics.data-an 新提交

The Fundaments of Unity: ${\mathcal O}(1)$ Couplings in Quantum Field Theories

统一的基础:量子场论中的 ${\mathcal O}(1)$ 耦合

Ben Allanach (Cambridge U., DAMTP)

AI总结 本文批判性地检验了基本量子场论中无量纲耦合应为量级1的预期,提出用展宽(最大与最小耦合模之比)量化该特性,并发现即使耦合服从独立同分布,比值可能远大于预期。

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Comments
15 pages, 3 figures
AI中文摘要

我们批判性地检验了在基本量子场论中,拉格朗日密度中的无量纲耦合应全部为量级1的预期。我们提出了一种衡量理论符合该预期的度量:展宽(此类无量纲耦合的模的最大值与最小值之比),并得到了各种闭式结果。如果我们采用独立同分布(IID)耦合来参数化对量级1耦合值的不确定性,则耦合的比值可能远大于朴素预期。例如,对于一个具有20个IID单位正态耦合的理论,其中两个耦合的模之比大于100的概率为0.29。即使IID耦合具有指数抑制的尾部,量级1耦合的比值分布也具有肥大的幂律尾部,且随独立耦合数量的增加而增长。

英文摘要

We critically examine the expectation that in a fundamental quantum field theory, dimensionless couplings in the Lagrangian density should all be of order unity. We propose a measure to quantify the adherence of a theory to this: the spread (the ratio of the largest to the smallest of the magnitudes) of such dimensionless couplings, obtaining various closed-form results. If we take independent identically distributed (IID) couplings to parameterise our uncertainty on the values of the order unity couplings, ratios of couplings can be much larger than one might naively expect. For a theory with 20 IID unit normal couplings, the probability that the magnitude of the ratio of two of them is greater than 100 is 0.29, for example. Even when the IID couplings have exponentially suppressed tails, the distribution of ratios of order one couplings has fat power-law tails which grow with the number of independent couplings.

2606.12391 2026-06-11 physics.plasm-ph physics.space-ph 新提交

Secondary drift-driven instabilities in the presence of a parallel-propagating electromagnetic ion cyclotron wave and cold multi-component ions

平行传播电磁离子回旋波与冷多组分离子存在下的次级漂移驱动不稳定性

Opal Issan, Patrick Kilian, Vadim Roytershteyn, Salomon Janhunen, Gian Luca Delzanno

AI总结 通过全动力学粒子模拟和线性理论,研究平行传播EMIC波驱动的次级不稳定性对冷等离子体的影响,发现次级波在低振幅下仍存在,并导致冷质子和氧离子的各向异性加热。

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AI中文摘要

电磁离子回旋(EMIC)波在地球内磁层中常见,尤其在环电流质子各向异性驱动的地磁暴期间。虽然它们在辐射带热离子散射中的作用已明确,但与冷(<100 eV)等离子体的相互作用仍知之甚少,部分原因是航天器充电阻碍冷离子到达仪器。已知平行传播EMIC波的电场可驱动种间垂直极化漂移,激发低混杂次级不稳定性。在多组分等离子体中,这些包括修正双流和离子-离子交叉场不稳定性。本文通过全动力学粒子模拟和线性理论,研究此类次级不稳定性对平行传播EMIC波和多组分等离子体的影响。我们发现,只要冷种群足够冷,次级波即使在低EMIC振幅下也存在。动力学模拟表明,这些次级模式产生冷质子和单电荷氧离子的各向异性加热,主要垂直于环境磁场方向,而电子则在平行和垂直方向均被加热。

英文摘要

Electromagnetic ion cyclotron (EMIC) waves are commonly observed in Earth's inner magnetosphere, particularly during geomagnetic storms driven by anisotropic ring-current protons. While their role in radiation belt scattering of hot ions is well established, their interaction with the cold (less than 100 eV) plasma remains less understood. This is partly due to limited magnetospheric cold ion observations, as spacecraft charging can prevent cold ions from reaching onboard instruments. It is well-known that the electric field of a parallel-propagating EMIC wave can drive inter-species perpendicular polarization drifts that excite lower-hybrid secondary instabilities. In multi-component plasmas, these include the modified two-stream and the ion-ion cross-field instabilities. In this paper, we study the impact of such secondary instabilities on the parallel-propagating EMIC wave and multi-component plasma via a fully kinetic particle-in-cell simulation and linear theory. We find that the secondary waves persist even at low EMIC amplitudes, provided the cold population remains sufficiently cold. The kinetic simulation demonstrates that these secondary modes produce anisotropic heating of cold protons and singly-charged oxygen ions, primarily in the direction perpendicular to the ambient magnetic field and of electrons in both parallel and perpendicular directions.

2606.12390 2026-06-11 astro-ph.HE 新提交

Time-dependent cosmic-ray escape from wind bubbles: hard spectra formation

从风泡中时间依赖的宇宙射线逃逸:硬谱形成

Lukas Merten, Sophie Aerdker, Enrico Peretti

AI总结 研究风泡中宇宙射线的时间依赖逃逸,通过求解含时输运方程发现逃逸谱可硬于E^{-2},且低能粒子可能被显著抑制,为多信使观测提供特征。

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AI中文摘要

概述:风驱动气泡是动态系统,根据其物理性质,可将宇宙射线加速到非常高的能量。我们研究粒子输运的时间依赖描述如何影响逃逸的宇宙射线通量。模型:风泡系统建模为球对称。宇宙射线在终止激波位置连续注入,通过对流和扩散传播,直到在作为自由逃逸边界的前向激波的时间依赖位置逃逸。方法:将一维球对称含时输运方程转化为相应的随机微分方程组,并使用开源宇宙射线传播框架CRPropa的修改版本进行积分。结果:我们发现,在风驱动阶段,风泡下游逃逸谱可以比扩散激波加速的传统预期$\sim E^{-2}$更硬。根据湍流模型,初始能谱在最低能量处可能被显著抑制,这可能是区分不同湍流实现的可观测特征。这种效应可能导致低能粒子的有效约束,从而在多信使辐射和气泡内累积的宇宙射线grammage方面产生可观测的影响。

英文摘要

Overview: Wind-driven bubbles are dynamic systems that can accelerate cosmic rays, depending on their physical properties, up to very high energies. We investigate how a time-dependent description of the particle transport may impact the escaping cosmic-ray flux. Model: The wind bubble system is modeled as spherically symmetric. Cosmic rays are continuously injected at the position of the termination shock and propagate through advection and diffusion until the escape at the time-dependent position of the forward shock, which is treated as a free escape boundary. Methods: The one-dimensional spherical time-dependent transport equation is solved by transforming it into the corresponding set of stochastic differential equations, and integrated with a modified version of the open source cosmic-ray propagation framework CRPropa. Results: We find that, during the wind driven phase, the downstream escaping spectra from wind bubbles can be harder than $\sim E^{-2}$, the conventional expectation from diffusive shock acceleration. Depending on the turbulence model the initial energy spectrum can be significantly suppressed at lowest energies, which could be an observable feature to distinguish between different turbulence realizations. This effect could lead to an efficient confinement of low energy particles, potentially leading to observable implication in terms of multi-messenger radiation and cosmic-ray accumulated grammage within the bubble.

2606.12389 2026-06-11 astro-ph.CO 新提交

KiDS-Legacy: Joint analysis of second- and third-order cosmic shear

KiDS-Legacy:二阶和三阶宇宙剪切联合分析

L. Linke, L. Porth, P. Burger, J. Harnois-Déraps, S. Heydenreich, P. Schneider, M. Asgari, M. Bilicki, C. Georgiou, C. Heymans, H. Hildebrandt, H. Hoekstra, P. Jalan, B. Joachimi, S. Joudaki, K. Kuijken, S. Li, L. Moscardini, M. Radovich, R. Reischke, B. Stölzner, A. H. Wright, Z. Yan, Y.-H. Zhang

AI总结 联合分析KiDS巡天的二阶和三阶宇宙剪切,使用COSEBIs和三阶孔径质量矩,显著收紧Ω_m约束并将Ω_m-S_8平面品质因子提高两倍以上。

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Comments
14 pages plus appendix, 15 figures, submitted to A&A
AI中文摘要

大尺度结构的弱引力透镜效应是一个强大的宇宙学探针。虽然大多数分析依赖于二阶相关,但这些主要对参数组合$S_8 = \sigma_8 (\Omega_m/0.3)^{0.5}$敏感,限制了它们独立约束$\Omega_m$和其他宇宙学参数的能力。高阶统计量捕捉密度场的非高斯特征,因此可以打破参数简并,从弱引力透镜巡天中提取更多宇宙学信息。我们展示了Kilo-Degree巡天最终数据发布(KiDS-Legacy)中二阶和三阶宇宙剪切的联合分析。我们将2'到300'尺度上的COSEBIs(完备正交E/B模积分集)与4'到32'尺度上的三阶孔径质量矩相结合,进行二阶和三阶统计量的联合分析。与之前的KiDS分析相比,我们实现了若干方法论上的进步:具有红移和质量依赖的内禀对齐模型、在多个流体动力学模拟上验证的重子修正模型,以及减切和源聚集的修正。在KiDS-Legacy中结合COSEBIs与三阶孔径质量统计得到$\Omega_m = 0.297^{+0.056}_{-0.040}$和$S_8 = 0.806^{+0.025}_{-0.023}$,显著收紧了$\Omega_m$约束,并且与仅两点分析相比,在$\Omega_m$-$S_8$平面上的品质因子提高了一倍以上。三阶测量通过了严格的内部一致性检验,与KiDS-Legacy两点约束、其他2+3点透镜结果以及普朗克CMB测量在$1\sigma$内完全一致,没有提供$S_8$张力的证据,并展示了三点宇宙剪切作为即将进行的巡天关键探针的成熟性。

英文摘要

Weak lensing by large-scale structure is a powerful cosmological probe. While most analyses rely on second-order correlations, these are primarily sensitive to the parameter combination $S_8 = \sigma_8 (\Omega_m/0.3)^{0.5}$, limiting their ability to constrain $\Omega_m$ and other cosmological parameters independently. Higher-order statistics capture non-Gaussian features of the density field and can therefore break parameter degeneracies and extract more cosmological information from weak lensing surveys. We present a joint analysis of second- and third-order cosmic shear in the final data release of the Kilo-Degree Survey (KiDS-Legacy). We combine COSEBIs (Complete Orthogonal Sets of E-/B-mode Integrals) at scales between 2' and 300' with third-order aperture mass moments at scales between 4' and 32' to perform a joint analysis of second- and third-order statistics. Compared to previous KiDS analyses, we implement several methodological advances: an intrinsic alignment model with redshift and mass dependence, a baryon correction model validated on multiple hydrodynamical simulations, and corrections for reduced shear and source clustering. Combining COSEBIs with third-order aperture mass statistics in KiDS-Legacy yields $\Omega_m = 0.297^{+0.056}_{-0.040}$ and $S_8 = 0.806^{+0.025}_{-0.023}$, significantly tightening the $\Omega_m$ constraints and more than doubling the figure of merit in the $\Omega_m$--$S_8$ plane compared to the two-point analysis alone. The third-order measurements pass stringent internal consistency tests, are fully compatible with the KiDS-Legacy 2-point constraints, other 2+3-point lensing results and with Planck CMB measurements within $1\sigma$, providing no evidence for an $S_8$ tension and demonstrating the maturity of 3-point cosmic shear as a key probe for forthcoming surveys.

2606.12383 2026-06-11 quant-ph 新提交

The Simplified Stabilizer ZX-Calculus is Minimal

简化稳定子ZX-演算是极小的

Harry K. Stoltz

AI总结 通过反模型论证,证明稳定子ZX-演算中红/绿紧致结构重合规则和双代数规则相对于连接性元规则都是必要的,从而确立arXiv:1709.08903中的规则集无冗余。

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Comments
15 pages
AI中文摘要

ZX演算的稳定子片段是该理论中最重要的片段之一。密切相关的Clifford+T片段是近似通用的(arXiv:1705.11151)。此外,稳定子演算可以用一小部分重写规则描述,其中大多数已被证明是必要的(arXiv:1709.08903)。然而,描述红/绿紧致结构重合和重要双代数定律的两条规则尚未被证明是必要的。我们提出了一个反模型风格的论证,表明这两条规则相对于Backens--Perdrix--Wang(arXiv:1709.08903)的连接性元规则都是单独必要的,从而确立了arXiv:1709.08903中提出的规则集没有冗余的重写规则。

英文摘要

The stabilizer fragment of the ZX calculus is amongst the most important fragments of the theory. The closely related Clifford+T fragment is approximately universal ( arXiv:1705.11151 ). Additionally, the stabilizer calculus can be described by a small collection of rewrites, most of which have been shown to be necessary ( arXiv:1709.08903 ). However, two rules, describing the red/green compact-structure coincidence and the important bialgebra law, had not been shown to be necessary. We present a countermodel-style argument showing that both of these rules are individually necessary relative to the connectivity meta-rule of Backens--Perdrix--Wang ( arXiv:1709.08903 ), and hence establish that the rule set presented in arXiv:1709.08903 has no redundant rewrite rule.

2606.12375 2026-06-11 cs.CE math.NA physics.comp-ph 新提交

A coupled finite element formulation for chemo-mechano-thermodynamical contact and its application to bonding and debonding

化学-力学-热力学接触的耦合有限元公式及其在粘接与脱粘中的应用

Roger A. Sauer

AI总结 提出一种基于Sauer等人接触理论的耦合有限元公式,用于模拟化学-力学-热力学大变形接触,重点研究粘接与脱粘的演化及其与机械和热接触状态的耦合,并通过多个算例验证其通用性。

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Comments
42 pages, 22 figures, 6 tables
AI中文摘要

本文提出了一种用于耦合化学-力学-热力学大变形接触的有限元公式。该公式基于Sauer等人(2022)的接触理论,包含六个耦合但独立的场:两个接触体的变形和温度,以及界面粘接场和界面温度。后者由界面处的化学和机械能量耗散控制。这里重点研究粘接和脱粘的演化,以及它们如何与机械和热接触状态耦合。基于二次接触势,提出了几个基本模型。由此产生的接触公式变得非常通用和灵活,通过几个具有挑战性的算例进行了说明。这些算例包括压力依赖和间隙依赖的粘接、放热粘接反应、热硬化和热膨胀,以及同时发生的粘接和脱粘。它们基于使用经典和等几何形函数以及隐式时间积分的整体有限元实现。还提供了牛顿-拉夫逊求解方法所需的完全线性化。如果粘接点是材料点,则粘接变量可以在局部凝聚掉。

英文摘要

This work presents a finite element formulation for coupled chemo-mechano-thermodynamical large deformation contact. The formulation is based on the contact theory of Sauer et al. (2022) that contains six coupled (but separate) fields: the deformation and temperature of the two contacting bodies, as well as an interfacial bonding field and interfacial temperature. The latter is governed by the chemical and mechanical energy dissipation at the interface. Here the focus is placed on the evolution of bonding and debonding, and how it is coupled to the mechanical and thermal contact state. Several elementary models are proposed for this based on a quadratic contact potential. The resulting contact formulation becomes very general and versatile, which is illustrated by several challenging examples. They include pressure- and gap- depended bonding, exothermic bonding reactions, thermal hardening and thermal expansion, as well as simultaneous bonding and debonding. They are based on a monolithic finite element implementation using classical and isogeometric shape functions together with implicit time integration. Its full linearization, required for the Newton-Raphson solution method, is also provided. If bonding sites are material points, the bonding variable can be condensed-out locally.

2606.12367 2026-06-11 hep-th cond-mat.stat-mech 新提交

Nonadditivity in Quantum Field Theory: Replica Energies, Scaling Filters, and the Renormalization Group

量子场论中的非加性:复制能量、标度滤波器与重整化群

Giacomo Santoni, Francesco Scardino

AI总结 通过复制能量${\cal E}$衡量配分函数标度失效,建立统计力学与量子场论的桥梁,并用于提取普适临界数据、重整化缺陷自由能及区分不同非加性来源。

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AI中文摘要

广延系统有一个简单的热力学特征:配分函数的对数随系统大小均匀标度。我们证明,这种标度的失效(由复制能量${\cal E}$衡量)为统计力学和量子场论之间提供了有用的桥梁。相关的微分算子$(1-\frac1d L\partial_L)$去除了$W=\log Z$中的主要体贡献,并分离出对边界、拓扑、缺陷、长程力或其他非加性来源敏感的部分。在量子场论中,这一热力学思想有两个密切相关的用途。对于普通的有限体积或球面配分函数,相同滤波器的适当高阶版本可去除局域抵消项并提取普适固定点数据,如中心荷、球面自由能$F$和欧拉反常系数$a$。对于具有纠缠缺陷的复制几何,相同的滤波原理给出了重整化的缺陷自由能。在$2+1$维中,其$n\to1$极限正是熵$F$函数。我们利用这一视角来区分普通的有限尺寸修正、有能隙相中依赖于拓扑的常数、亚广延分形简并度,以及具有长程相互作用的真正非广延系统(如自引力热物质)。因此,复制能量为加性、缺陷自由能和重整化群不可逆性提供了一种共同的热力学语言。

英文摘要

Extensive systems have a simple thermodynamic signature: the logarithm of the partition function scales homogeneously with the size of the system. We show that the failure of this scaling, measured by the replica energy ${\cal E}$, provides a useful bridge between statistical mechanics and quantum field theory. The associated differential operator $(1-\frac1d L\partial_L)$ removes the leading bulk contribution to $W=\log Z$ and isolates the part that is sensitive to boundaries, topology, defects, long-range forces, or other sources of nonadditivity. In quantum field theory this thermodynamic idea has two closely related uses. For ordinary finite-volume or spherical partition functions, suitable higher-order versions of the same filter remove local counterterms and extract universal fixed-point data such as the central charge, the sphere free energy $F$, and the Euler anomaly coefficient $a$. For replica geometries with entangling defects, the same filtering principle gives the renormalized defect free energy. In $2+1$ dimensions, its $n\to1$ limit is precisely the entropic $F$-function. We use this perspective to distinguish ordinary finite-size corrections, topology-dependent constants in gapped phases, subextensive fracton degeneracies, and genuinely nonextensive systems with long-range interactions such as self-gravitating thermal matter. Replica energy therefore offers a common thermodynamic language for additivity, defect free energies, and renormalization-group irreversibility.

2606.12363 2026-06-11 quant-ph 新提交

Fermions are fundamentally more nonlocal than Bosons

费米子本质上比玻色子更非局域

Fatemeh Moradi Kalarde, Sadra Boreiri, Xiangling Xu, Lucas Tendick, Salman Beigi, Paolo Perinotti, Tommaso Guaita, Marc-Olivier Renou

AI总结 通过量子网络传输的不可区分费米子能产生比可区分粒子或不可区分玻色子更强的关联,证明费米子本质上更非局域,并引入费米子反交换和不可区分性作为操作资源。

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Comments
66 pages, 9 figures; Supplementary Materials (55 pages + 7 figures) included. Comments welcome!
AI中文摘要

贝尔定理表明,纠缠的量子粒子可以展现出经典粒子在没有额外非局域资源(如通信)的情况下无法复现的关联。在这个意义上,量子粒子本质上比经典粒子更非局域,纠缠在物理学中变得不可避免。这里我们在量子理论内部证明了类似的结果:通过量子网络传输的不可区分费米子可以产生可区分粒子或不可区分玻色子在没有额外通信的情况下无法复现的关联。在同样的意义上,费米子本质上比玻色子或可区分粒子更非局域,从而激励费米子反交换和不可区分性作为不可避免的操作资源。我们的结果进一步表明,对于某些分布式计算任务,费米子可以严格超越所有基于量子比特的协议,证明对信息处理的完整理解需要超越量子比特,走向费米子信息载体——febit。

英文摘要

Bell's theorem shows that entangled quantum particles can exhibit correlations that classical particles cannot reproduce without an additional nonlocal resource, such as communication. In this sense, quantum particles are fundamentally more nonlocal than classical ones, and entanglement becomes unavoidable in physics. Here we prove the analogous result within quantum theory itself: indistinguishable fermions transmitted through a quantum network can generate correlations that distinguishable particles or indistinguishable bosons cannot reproduce without additional communication. In the same sense, fermions are fundamentally more nonlocal than bosons or distinguishable particles, motivating fermionic anticommutation and indistinguishability as unavoidable operational resources. Our result further implies that fermions can strictly surpass all qubit-based protocols for certain distributed computing tasks, demonstrating that a complete understanding of information processing requires going beyond qubits to fermionic information carriers - febits.

2606.12361 2026-06-11 astro-ph.SR 新提交

Three-Phase Evolution of Aspect Ratio in Fast and Slow CMEs from the Sun to 1 AU

快速与慢速日冕物质抛射从太阳到1 AU的纵横比三相演化

Wageesh Mishra, Anjali Agarwal, Nandita Srivastava

AI总结 利用多视角日冕仪观测和GCS模型,结合1 AU处磁云原位测量,发现CME纵横比呈现低日冕上升、中间饱和、行星际下降的三相演化,且快速CME早期膨胀更强,慢速CME则更平缓。

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Comments
16 pages, 6 figures, 3 tables; Accepted for publication in MNRAS
AI中文摘要

日冕物质抛射(CME)在从太阳传播到1 AU的过程中经历显著的几何演化,影响其径向尺寸、膨胀和空间天气影响。我们研究了四个快速和四个慢速地球定向CME的纵横比和膨胀动力学演化。利用多视角日冕仪观测,结合渐变圆柱壳(GCS)模型和1 AU处相关磁云(MC)的校正原位测量,我们追踪了从低中冕到行星际空间的纵横比演化。我们发现纵横比并非恒定,而是呈现系统的三相演化:低中冕($\lesssim10$-$15\\,R_{\odot}$)的上升相、中间高度的饱和相,以及行星际空间的下降相。径向膨胀速度与前缘速度之比($V_{\rm exp}/V_{\rm LE}$)从日冕到1 AU显著下降,表明行星际传播过程中径向膨胀效率降低。纵横比和$V_{\rm exp}/V_{\rm LE}$的一致演化表明,从日冕中磁主导的膨胀过渡到日益受日球层环境控制的机制。我们注意到,快速CME表现出更强的早期膨胀,演变为更大、更径向延伸的结构,而慢速CME则呈现更平缓的上升和更陡峭的下降。这些结果表明,CME几何形状在传播过程中显著演化,并强调需要在模型中纳入纵横比演化,以改进对CME尺寸、到达时间和地磁效应的预测。

英文摘要

Coronal mass ejections (CMEs) undergo significant geometric evolution as they propagate from the Sun to 1 AU, influencing their radial size, expansion, and space weather impact. We investigate the evolution of CME aspect ratio and expansion dynamics for four fast and four slow Earth-directed CMEs. Using multipoint coronagraphic observations with the Graduated Cylindrical Shell (GCS) model and corrected in situ measurements of associated magnetic clouds (MCs) at 1 AU, we track the evolution of aspect ratio from the low-middle corona to interplanetary space. We find that aspect ratio does not remain constant but exhibits a systematic three-phase evolution: a rise phase in the low-middle corona ($\lesssim10$-$15\,R_{\odot}$), a saturation phase at intermediate heights, and then a decline phase in the interplanetary space. The ratio of radial expansion speed to leading-edge speed ($V_{\rm exp}/V_{\rm LE}$) decreases substantially from the corona to 1 AU, indicating a reduction in radial expansion efficiency during interplanetary propagation. The consistent evolution of aspect ratio and $V_{\rm exp}/V_{\rm LE}$ suggests a transition from magnetically dominated expansion in the corona to a regime increasingly controlled by the heliospheric environment. We note that fast CMEs show stronger early expansion and evolve into larger, more radially extended structures, whereas slow CMEs exhibit a more gradual rise and a steeper decline. These results demonstrate that CME geometry evolves significantly during propagation and highlight the need to incorporate aspect ratio evolution in models to improve predictions of CME size, arrival time, and geoeffectiveness.

2606.12358 2026-06-11 hep-lat 新提交

Lattice chiral non-Abelian gauge symmetry via bosonization

通过玻色化实现晶格手征非阿贝尔规范对称性

Soma Onoda

AI总结 基于非阿贝尔玻色化,提出二维非阿贝尔手征规范理论的晶格公式,通过引入规范中性旁观费米子并构造带三维体扩展的规范Wess-Zumino-Witten模型,在有限格距下实现反常抵消机制。

详情
Comments
48 pages, 3 figures
AI中文摘要

在手征规范理论的晶格公式中,一个核心问题是如何在有限格距下实现连续场论的反常抵消机制。本文基于非阿贝尔玻色化,提出了对应于二维非阿贝尔手征规范理论的玻色理论的晶格公式。在连续理论中,手征费米子的规范反常在玻色化描述中表现为来自规范Wess-Zumino-Witten模型所包含的三维Chern-Simons型体贡献的反常流入。受此结构启发,我们引入规范中性的旁观费米子,并利用由此产生的玻色化描述。然后,我们在适当的平滑条件下,构造了带三维体扩展的规范Wess-Zumino-Witten模型的晶格对应。该晶格公式的一个显著特征是指数化作用量中左右体贡献的抵消。当满足无反常条件,即左右表示具有相同的二次指标时,这种抵消甚至在取连续极限之前就发生。因此,本构造通过二维无反常手征规范理论的玻色化描述,在有限格距下实现了反常抵消机制。建立所需的连续极限仍然是一个重要的开放问题。

英文摘要

A central issue in lattice formulations of chiral gauge theories is how the anomaly cancellation mechanism of the continuum theory can be realized at finite lattice spacing. In the present paper, based on non-Abelian bosonization, we propose a lattice formulation of the bosonic theory corresponding to a two-dimensional non-Abelian chiral gauge theory. In the continuum theory, the gauge anomaly of chiral fermions is represented, in the bosonized description, as anomaly inflow from a three-dimensional Chern--Simons-type bulk contribution contained in a gauged Wess--Zumino--Witten model. Motivated by this structure, we introduce gauge-neutral spectator fermions and use the resulting bosonized description. We then construct a lattice counterpart of the gauged Wess--Zumino--Witten model with a three-dimensional bulk extension under appropriate smoothness conditions. A salient feature of this lattice formulation is the cancellation of the left and right bulk contributions in the exponentiated action. This cancellation occurs even before taking the continuum limit when the anomaly-free condition is satisfied, namely when the left and right representations have identical quadratic indices. Thus, the present construction realizes the anomaly-cancellation mechanism at finite lattice spacing via the bosonized description of two-dimensional anomaly-free chiral gauge theories. Establishing the desired continuum limit remains an important open problem.

2606.12356 2026-06-11 astro-ph.HE 新提交

Stellar mass loading drives dissipation and reacceleration in AGN jets: Explaining VLBI-Gaia offsets and constraining jet power

恒星质量加载驱动AGN喷流中的耗散和再加速:解释VLBI-Gaia偏移并约束喷流功率

G. Fichet de Clairfontaine, M. Perucho, J. M. Martí, Y. Y. Kovalev

AI总结 通过RMHD模拟和辐射转移计算,发现恒星风质量加载在特定喷流功率范围内产生射电-光学质心偏移,可用于约束喷流功率和喷流-宿主耦合。

详情
Comments
Accepted for publication in A&A
AI中文摘要

最近的甚长基线干涉测量(VLBI)和Gaia天体测量揭示了活动星系核(AGN)射电和光学质心之间存在系统性的毫角秒级偏移。这些“射电-光学偏移”并不改变标准的光深依赖的射电核心位移解释。相反,它们表明光学发射质心经常位于射电同步辐射光深$\tau = 1$面的下游,这意味着在相对论性喷流中,除了光深射电核心之外,还存在额外的耗散和粒子再加速。我们进行了AGN喷流的稳态轴对称相对论磁流体动力学(RMHD)模拟,包括来自恒星风的重子质量加载,并变化喷流动能和恒星核心半径。通过辐射传输代码生成射电和光学波段的合成同步辐射图像,并提取质心偏移以与观测比较。仅当喷流功率$L_{\rm j} \sim 10^{42.5} - 10^{44}\\,\rm{erg}\\,\rm{s}^{-1}$时,才出现秒差距尺度的射电-光学偏移。在此范围内,恒星风在固有距离约$10^2-10^3\\,\rm{pc}$处触发喷流减速,将光学质心向下游移动,产生约$0.1 - 4\\,\rm{mas}$(在$z=1$处对应几十秒差距)的偏移。偏移依赖于恒星分布、视角和光学喷流主导性,并在此功率范围外消失。我们重现了观测到的偏移发生率随红移的演化,将其与热脉动渐近巨星分支(TP-AGB)质量损失的宇宙演化联系起来。尽管恒星质量加载不太可能是唯一的耗散机制,但它在星系核中不可避免的存在使其成为能量耗散的自然基线。因此,射电-光学偏移为约束AGN喷流功率和喷流-宿主耦合提供了独立于传统射电瓣方法的手段。

英文摘要

Recent Very Long Baseline Interferometry (VLBI) and Gaia astrometry reveal systematic milliarcsecond-scale offsets between the radio and optical centroids of active galactic nuclei (AGN). These "radio-optical offsets" do not alter the standard opacity-driven interpretation of radio core shifts. Instead, they indicate that the optical emission centroid is frequently displaced downstream of the radio synchrotron optical depth $\tau = 1$ surface, implying that additional dissipation and particle reacceleration occur beyond the opacity radio core within relativistic jets. We perform steady-state, axisymmetric relativistic magnetohydrodynamic (RMHD) simulations of AGN jets, including baryonic mass-load from stellar winds, varying jet kinetic power, and stellar core radius. Synthetic synchrotron emission maps in radio and optical bands are generated via a radiative transfer code, and centroid offsets are extracted for comparison with observations. Parsec-scale radio-optical offsets arise only for jet powers $L_{\rm j} \sim 10^{42.5} - 10^{44}\,\rm{erg}\,\rm{s}^{-1}$. In this regime, stellar winds trigger jet deceleration at intrinsic distances of a few $10^2-10^3\,\rm{pc}$, shifting the optical centroid downstream and producing offsets of $\sim 0.1 - 4\,\rm{mas}$ (a few tens of parsecs at $z=1$). Offsets depend on stellar distribution, viewing angle, and optical jet dominance, and vanish outside this power range. We reproduce the observed redshift evolution of offset incidence, linking it to the cosmic evolution of thermally pulsing asymptotic giant branch (TP-AGB) mass loss. Although stellar mass loading is unlikely to be the sole dissipation mechanism, its unavoidable presence in galactic nuclei makes it a natural baseline for energy dissipation. Radio-optical offsets therefore offer a constraint on AGN jet power and jet-host coupling, independent of traditional lobe-based methods.

2606.12355 2026-06-11 astro-ph.GA 新提交

Between Degeneracy and Evolution: UV-to-optical Insights into the BH$^*$ Model in Little Red Dots

介于简并与演化之间:来自紫外-光学波段对小红点中BH$^*$模型的洞察

Rosa M. Mérida, Marcin Sawicki, Chris J. Willott, Gaia Gaspar, Kartheik G. Iyer

AI总结 对66个小红点(LRDs)进行紫外-光学连续谱拟合,发现仅约6%的LRDs由BH$^*$模型最佳描述,大多数以恒星或AGN为主,表明BH$^*$与其他模型存在强简并性。

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Comments
22 pages, 15 figures, 4 tables. Submitted for publication in A&A
AI中文摘要

小红点(LRDs)是一类异质性天体,已有多种关于其物理本质和演化的理论模型。尽管这些理论已利用有限的光谱特征对个别LRDs进行了检验,但尚缺乏在宽波段范围内结合不同模型对LRD群体进行系统性贝叶斯分析。本研究利用JWST/NIRSpec PRISM光谱,对66个红移2<z<6的LRDs进行一致的紫外(UV)-光学连续谱拟合。采用修改版的Bagpipes——包括受巴尔默吸收影响的黑体(BB)辐射、经尘埃衰减的恒星和星云发射,以及活动星系核(AGN)成分——评估黑洞星(BH*)模型描述LRD群体的表现。我们采用宽先验,因此不施加任何特定的物理场景。结果显示,在具有统计稳健解的52个LRDs中,仅约6%在光学波段由BH*最佳拟合、在紫外波段由宿主星系最佳拟合。约8%的LRDs表现出BB主导的光学连续谱,但缺乏恒星成分或显示AGN紫外泄漏。大多数LRDs在光学波段由恒星和/或AGN发射主导,BB贡献较小。当我们采用不偏好强AGN连续谱的先验以强制BH*类解时,BH$^*$系统的比例增加到约40%,突显了BH*解与替代模型之间的强简并性。即使强制BH*类解,许多LRDs仍需要恒星主导的光学连续谱。这可能揭示了BH*模型的局限性,或指向一个演化序列:随着宿主增长,BB贡献减少,导致在较低红移处BB温度降低、恒星质量增大。在此情景下,更明显的“V”形对应LRD演化的较晚阶段。

英文摘要

Little Red Dots (LRDs) are a heterogeneous class of objects, with several proposed scenarios for their physical nature and evolution. While these theories have been tested on individual LRDs using limited spectral features, a systematic Bayesian analysis of the LRD population incorporating the different models across a broad wavelength range is still lacking. In this study, we conduct a consistent ultraviolet (UV)-to-optical continuum fitting analysis of 66 LRDs at 2<z<6 using JWST/NIRSpec PRISM spectroscopy. Employing a modified version of Bagpipes--including blackbody (BB) emission affected by Balmer absorption, stellar and nebular emission attenuated by dust, and an active galactic nucleus (AGN) component--we assess the performance of the black hole star (BH*) model in describing the LRD population. We adopt broad priors and therefore do not impose any specific physical scenario. Our results show that only ~6% of LRDs with statistically robust solutions (52 objects in total) are best-fit by a BH* in the optical and a host galaxy in the UV. ~8% of LRDs show BB-dominated optical continua but lack a stellar component or exhibit AGN UV leakage. Most LRDs are dominated by stellar and/or AGN emission in the optical, with minor BB contribution. When we adopt a prior that disfavors a strong AGN continuum to enforce BH*-like solutions, the percentage of BH$^*$ systems increases to ~40%, highlighting the strong degeneracy between a BH* solution and alternative scenarios. Even when BH*-like solutions are enforced, many LRDs still require a stellar-dominated optical continuum. This may reveal limitations of the BH* model or point to an evolutionary sequence in which the BB contribution decreases as the host grows, leading to lower BB temperatures and higher stellar masses at lower z. In this scenario, more pronounced ''V'' shapes would correspond to later stages in LRD evolution.

2606.12353 2026-06-11 cond-mat.mes-hall quant-ph 新提交

Gate-tunable spin-valley transport via carrier velocity in monolayer WSe$_2$

单层WSe$_2$中通过载流子速度实现栅极可调的自旋-谷输运

Otman Bouladiane, Hocine Bahlouli, Clarence Cortes, David Laroze, Ahmed Jellal

AI总结 基于有效大质量狄拉克哈密顿量,理论研究了单层WSe$_2$中自旋和谷分辨的量子输运,发现通过调控势垒速度、标量势等参数可连续调节自旋-谷极化电流的幅值和方向。

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Comments
11 pages, 9 figures
AI中文摘要

我们理论研究了由有效大质量狄拉克哈密顿量描述的单层二硒化钨(WSe$_2$)中自旋和谷分辨的量子输运。特别关注一个有限势垒区域,其特征是同时调制的费米速度和标量势。势垒速度$v_2$通过速度比$\xi=v_2/v_1$与外部速度$v_1$相关联,这是受斯涅尔-笛卡尔定律的光学类比启发。精确的折射条件取决于完整的自旋和谷分辨色散,而简单的比例$\xi=v_2/v_1$仅在无质量对称极限下恢复。导带和价带中由$\lambda_c$和$\lambda_v$量化的本征自旋-轨道耦合与自旋和谷依赖的塞曼场$M_s$和$M_v$的相互作用导致准粒子色散发生显著变化,从而引起输运特性的显著改变。通过求解狄拉克方程并在界面处施加电流守恒匹配条件,我们计算了自旋和谷依赖的透射概率和电导。我们的结果表明,势垒速度、标量势、入射角、入射能量和势垒宽度可作为输运的有效控制参数,产生强各向异性和共振隧穿特征。此外,我们展示了自旋和谷极化电流的幅值和方向可以通过速度和势垒调制连续调节。这些发现确立了速度和势垒联合工程作为控制二维过渡金属二硫族化物中自旋-谷物理的强大理论框架。

英文摘要

We theoretically investigate spin- and valley-resolved quantum transport in monolayer tungsten diselenide (WSe$_2$) described by an effective massive Dirac Hamiltonian. Particular attention is devoted to a finite barrier region characterized by simultaneously modulated Fermi velocity and scalar potential. The barrier velocity $v_2$ is related to the external velocity $v_1$ through a velocity ratio $\xi=v_2/v_1$, motivated by an optical analogy with the Snell-Descartes law. The exact refraction condition depends on the full spin- and valley-resolved dispersion, and the simple ratio $\xi=v_2/v_1$ is recovered only in the massless, symmetric limit. The interplay of intrinsic spin-orbit coupling in the conduction and valence bands, quantified by $\lambda_c$ and $\lambda_v$, with spin- and valley-dependent Zeeman fields, $M_s$ and $M_v$, gives rise to substantial changes in the quasiparticle dispersion, leading to pronounced modifications of the transport characteristics. By solving the Dirac equation and enforcing current-conserving matching conditions at the interfaces, we compute the spin- and valley-dependent transmission probability and conductance. Our results demonstrate that the barrier velocity, scalar potential, incidence angle, incident energy, and barrier width serve as effective control parameters for transport, giving rise to strong anisotropy and resonant tunneling features. Furthermore, we show that both the magnitude and orientation of spin- and valley-polarized currents can be continuously tuned via velocity and potential modulation. These findings establish combined velocity and potential engineering as a powerful theoretical framework for controlling spin-valley physics in two-dimensional transition-metal dichalcogenides.

2606.12347 2026-06-11 cs.CE physics.geo-ph 新提交

Local Stress Redistribution Controls Interactions between Hydraulic Fractures and Pre-existing Fractures

局部应力重分布控制水力裂缝与预先存在裂缝之间的相互作用

S. Shandilaya, M. Alaleeli, S.H. Kim, M. Mobasher, S. Roshankhah

AI总结 通过实验和模拟,研究了天然裂缝诱导的应力重分布如何控制水力裂缝的轨迹,揭示了剪切变形对裂缝吸引或排斥的作用机制。

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Comments
24 pages, 12 figures. Submitted to the International Journal of Rock Mechanics and Mining Sciences
AI中文摘要

水力裂缝在天然裂缝性地层中的传播受到预先存在的天然裂缝附近局部应力状态的强烈影响。天然裂缝诱导的剪切变形和应力重分布在控制水力裂缝轨迹中的作用仍不明确。本研究通过耦合实验室实验和孔隙弹性扩展有限元模拟,在平面应变条件下对完整和预裂PMMA试样进行了研究,探讨了天然裂缝诱导的应力重分布如何控制水力裂缝与天然裂缝的相互作用。数字图像相关提供了机械加载和水力压裂过程中位移和应变演化的全场测量。在固定底座、侧向约束和垂直压缩边界条件下,倾斜的天然裂缝诱导不对称的应力重分布和剪切变形,在流体注入前产生不同的局部应力状态。结果表明,水力裂缝轨迹由天然裂缝相对于远场最大主应力方向产生的剪应力和剪应变分量的符号和空间分布控制。促进天然裂缝附近压应力发展的剪切变形导致水力裂缝偏转远离,而降低天然裂缝有效法向应力的剪切变形则促进裂缝吸引和连接。预裂试样中水力裂缝曲率的相应数值再现需要混合模式(I-II型)断裂能释放准则,而完整试样则纯I型扩展。总体而言,研究结果揭示了由于天然裂缝的存在,局部应力状态演化导致从拉伸张开到剪切辅助混合模式传播的转变,为地下刺激和储存应用中预测和控制裂缝轨迹提供了机理基础。

英文摘要

Hydraulic fracture (HF) propagation in naturally fractured formations is strongly influenced by local stress states near pre-existing natural fractures (NFs). The role of NF-induced shear deformation and stress redistribution in controlling HF trajectories remains poorly characterized. This study investigates how NF-induced stress redistribution governs HF-NF interactions through coupled laboratory experiments and poroelastic extended finite element simulations on intact and pre-fractured PMMA specimens under plane-strain conditions. Digital image correlation provides full-field measurements of displacement and strain evolution during mechanical loading and hydraulic fracturing. Under fixed-base, lateral confinement, and vertical compression boundary conditions, inclined NFs induce asymmetric stress redistribution and shear deformation, generating distinct local stress states prior to fluid injection. The results demonstrate that the HF trajectory is governed by the sign and spatial distribution of shear stress and shear strain components generated by NF orientation relative to the far-field maximum principal stress. Shear deformation that promotes compressive stress development adjacent to the NF causes the HF to deflect away, whereas shear deformation that reduces the effective normal stress along the NF promotes fracture attraction and linkage. Corresponding numerical reproduction of HF curvature in pre-fractured specimens requires mixed-mode (Mode I-II) fracture energy release criteria, while the intact specimen propagates in pure Mode I. Overall, the findings reveal a transition from tensile opening to shear-assisted mixed-mode propagation as local stress states evolve due to the presence of NFs, providing a mechanistic basis for predicting and controlling fracture trajectories in subsurface stimulation and storage applications.

2606.12338 2026-06-11 hep-th quant-ph 新提交

Entanglement generation between field modes mediated by a fluctuating conducting wall

由涨落导体壁介导的场模之间的纠缠生成

Luca Giovanni Cammarata, Tommaso Fazio, Roberto Passante, Lucia Rizzuto

AI总结 研究一个可移动导体板在两个固定板之间量子涨落下,通过推广的Law哈密顿量描述系统,微扰计算发现两个子腔中的场模之间存在纠缠,并分析了物理参数对纠缠量的影响。

详情
Comments
10 pages, 6 figures
AI中文摘要

我们考虑一个质量有限的、在两个固定板之间可移动的导体板,其机械自由度被量子力学处理,并通过谐振子势束缚在其平衡位置。因此,可移动壁受到其位置的量子涨落。这创建了一个由可移动涨落板分隔的两个子腔系统,以及两个无质量的一维标量场,每个子腔中各有一个。该系统由Law哈密顿量的适当推广来描述。可移动壁的存在产生了有效的板-场相互作用,以及场模之间的有效相互作用。我们在微扰论的第二阶,通过迹掉壁的自由度,得到了相互作用系统的基态以及每个子腔中场的约化密度算符。我们通过解析计算负性来评估两个子腔中各一个场模之间的纠缠;然后数值计算了总多模负性。我们的结果表明,在两种情况下,两个子腔中的场都是纠缠的,这与壁固定在空间中的情况形成对比。我们讨论了场纠缠量作为系统相关物理参数(如可移动壁的质量和振荡频率、其与固定壁的距离以及所考虑的场模频率)的函数。

英文摘要

We consider a movable conducting plate of finite mass, between two fixed ones, whose mechanical degrees of freedom are treated quantum-mechanically and bound to its equilibrium position by a harmonic potential. The movable wall is thus subjected to quantum fluctuations of its position. This creates a system of two sub-cavities separated by the movable fluctuating plate, and two massless one-dimensional scalar fields, one in each sub-cavity. This system is described by an appropriate generalization of the Law Hamiltonian. The presence of the movable wall yields an effective plate-fields interaction, as well as an effective interaction between the field modes. We obtain, at the second order in perturbation theory, the ground state of the interacting system and the reduced density operator of the fields in each sub-cavity by tracing out the wall's degrees of freedom. We calculate the entanglement between two field modes, one in each cavity, by evaluating analytically the negativity; we then evaluate numerically also the total multimode negativity. Our results show that in both cases the fields in the two sub-cavities are entangled, in contrast to the case in which the wall is fixed in space. We discuss the amount of the field entanglement present as a function of relevant physical parameters of the system such as the mass and oscillation frequency of the movable wall, its distance from the fixed walls and the frequencies of the field modes considered.

2606.12326 2026-06-11 physics.chem-ph 新提交

Transferable Machine Learning of Electronic Hamiltonians with Superposition-of-Atomic-Potentials Features

基于原子势叠加特征的可迁移电子哈密顿量机器学习

Chaoqun Zhang, Christian Venturella, Enzhi Chen, Tianyu Zhu

AI总结 提出基于原子势叠加(SAP)近似的哈密顿量学习框架,结合对称性适配的原子轨道学习基和轨道图神经网络预测Kohn-Sham Fock矩阵,并通过降维方案扩展到大基组,在QM9和有机电荷传输材料中实现高精度可迁移预测。

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AI中文摘要

电子哈密顿量的机器学习为电子波函数和物理可观测量提供了一条统一途径。我们引入了一个哈密顿量学习框架,该框架基于从原子势叠加(SAP)近似导出的电子特征,这是一种有效的自洽场初始猜测,能够捕获基本的电子-电子屏蔽效应。SAP量定义了一个对称性适配的本征原子轨道学习基,并为基于轨道的图神经网络提供物理信息输入,该网络预测收敛的Kohn-Sham Fock矩阵。为了将方法扩展到更大的基组,我们进一步开发了一个降维方案,从最小基组特征预测大基组电子结构。在QM9数据集上,该模型准确再现了前沿和核心轨道能量、偶极矩以及完整态密度。对于有机电荷传输材料,它产生了苯、四氰基对苯二醌二甲烷(TCNQ)和四硫富瓦烯(TTF)二聚体的精确分子间转移积分,并迁移到未见过的取代苯异质二聚体,平均绝对误差为4.8 meV。这些结果确立了基于SAP的电子哈密顿量机器学习作为高通量电子结构预测的可迁移且可扩展的工具。

英文摘要

Machine learning (ML) of electronic Hamiltonians offers a unified route to electronic wave functions and physical observables. We introduce a Hamiltonian learning framework built on electronic features derived from the superposition-of-atomic-potentials (SAP) approximation, an efficient self-consistent-field initial guess that captures essential electron-electron screening. SAP quantities define a symmetry-adapted intrinsic atomic orbital learning basis and provide physics-informed inputs to an orbital-based graph neural network that predicts converged Kohn-Sham Fock matrices. To extend the approach to larger basis sets, we further develop a downfolding scheme that predicts large-basis electronic structure from minimal-basis features. On the QM9 dataset, the model accurately reproduces frontier and core orbital energies, dipole moments, and the full density of states. For organic charge-transport materials, it yields accurate intermolecular transfer integrals for benzene, tetracyanoquinodimethane (TCNQ), and tetrathiafulvalene (TTF) dimers, and transfers to unseen substituted-benzene heterodimers with a mean absolute error of 4.8 meV. These results establish SAP-based ML of electronic Hamiltonians as a transferable and scalable tool for high-throughput electronic-structure prediction.

2606.12323 2026-06-11 physics.atom-ph 新提交

Photon Cycling and Laser Cooling of an Asymmetric Top Molecule

不对称陀螺分子的光子循环与激光冷却

Grace K. Li, Giseok Lee, Jack Mango, Hana Lampson, YongWoong Lee, Winston Wang, Avikar Periwal, Nathaniel B. Vilas, Alexander Frenett, Loïc Anderegg, John M. Doyle

AI总结 通过光学泵浦实现振动态闭合,驱动特定转动跃迁保持转动闭合,首次将激光冷却扩展到不对称陀螺分子,为量子信息和新物理搜索开辟新途径。

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Comments
6 pages, 5 figures
AI中文摘要

我们实现了不对称陀螺分子(ATM)——单酰胺钙(CaNH$_2$)的二维磁辅助西绪福斯激光冷却。通过光学泵浦$X[3_1]$态,实现了$41.1 \pm 6.3$个光子散射的振动态闭合。光子循环测量与色散荧光光谱确定的支化比吻合良好。通过驱动$X[1_{11}] \to A [0_{00}]$跃迁保持转动闭合。未观察到额外的态泄漏通道,这拓宽了分子激光冷却的范围,将ATM包括在内,ATM是最一般的几何分子类别,具有最丰富的内部结构。未来量子控制的ATM应用包括新的量子信息平台和超越标准模型的物理搜索。

英文摘要

We realize two-dimensional magnetically-assisted Sisyphus laser cooling of an asymmetric top molecule (ATM), calcium monoamide (CaNH$_2$). Vibrational state closure is achieved with $41.1 \pm 6.3$ photons scatters using optical pumping of the $X[3_1]$ state. Photon-cycling measurements show good agreement with branching ratios determined by dispersed fluorescence spectroscopy. Rotational closure is maintained by driving the $X[1_{11}] \to A [0_{00}]$ transition. The observed absence of additional state leakage channels broadens the scope of molecular laser cooling to include ATMs, which are the most general geometric class of molecules and possess the richest internal structure. Future applications of quantum controlled ATMs include new quantum information platforms and searches for physics beyond the Standard Model.

2606.12322 2026-06-11 physics.plasm-ph physics.comp-ph 新提交

Mixed Hermite-Legendre spectral method for kinetic plasma simulations

混合Hermite-Legendre谱方法用于动理学等离子体模拟

Opal Issan, Gian Luca Delzanno, Vadim Roytershteyn

AI总结 提出混合Hermite-Legendre谱方法,通过约束条件守恒质量、动量和能量,在相同自由度下比单一方法更精确地处理速度空间局部非麦克斯韦特征。

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AI中文摘要

动理学无碰撞等离子体方程通常通过速度空间的谱方法求解。最常用的谱方法基于带有麦克斯韦权重的Hermite多项式,因为该基函数能以较少的自由度高效表示近麦克斯韦分布。另一种方法使用Legendre多项式,更适合解析强非麦克斯韦特征。本文提出一种结合Hermite和Legendre展开的混合方法。该方法对于非麦克斯韦特征在速度空间中局部化的问题(如束流和平坦区)特别有利。我们通过施加某些约束,从解析和数值上证明混合方法守恒总质量、动量和能量。数值结果表明,在相同自由度下,与单独的Hermite或Legendre方法相比,所提出的混合方法能在保持可比计算成本的同时提高精度。

英文摘要

Kinetic collisionless plasma equations are commonly solved via spectral methods in velocity space. The most commonly used spectral method is based on Hermite polynomials with a Maxwellian weight, as this basis efficiently represents near-Maxwellian distributions with relatively few degrees of freedom. An alternative approach uses Legendre polynomials, which are better suited for resolving strongly non-Maxwellian features. In this paper, we propose a mixed method that combines the Hermite and Legendre expansions. The mixed method is particularly advantageous for problems in which non-Maxwellian features are localized in velocity space, such as beams and plateaus. We demonstrate analytically and numerically that the mixed method conserves total mass, momentum, and energy by imposing certain constraints. The numerical results show that, for the same number of degrees of freedom, the proposed mixed method can achieve improved accuracy in comparison to the individual Hermite or Legendre methods, while maintaining comparable computational cost.

2606.12313 2026-06-11 quant-ph 新提交

Quantum repeater segment with free-space coupled co-trapped ions using telecom photon interference

利用电信光子干涉的自由空间耦合共俘获离子的量子中继段

Max Bergerhoff, Pascal Baumgart, Christian Haen, Jonas Meiers, Tobias Bauer, Jonas Haferkamp, Christoph Becher, Jürgen Eschner

AI总结 通过共俘获自由空间耦合的40Ca+离子发射光子,转换至电信C波段并经过440米光纤传输后干涉,进行光子贝尔测量创建存储器间纠缠,实现保真度≥68(8)%的纠缠Bell态。

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Comments
11 pages, 7 figures
AI中文摘要

量子中继段是量子中继器的基本构建模块,可生成量子存储器的缓冲纠缠以连接量子中继单元,也可实现量子计算机之间的连接。在我们提出的实现方案中,从两个共俘获的自由空间耦合$^{40}$Ca$^+$离子发射的光子被转换到电信C波段,并在经过440米光纤(每臂220米)传输后发生干涉,通过光子贝尔测量在存储器之间创建纠缠。利用该方案,我们生成了一个保真度$\ge 68(8)\%$的纠缠$\left|\Psi^+\right\rangle$贝尔态,突显了俘获$^{40}$Ca$^+$离子作为有前景的量子中继硬件平台的优势。

英文摘要

A quantum repeater segment is a basic building block of a quantum repeater, generating buffered entanglement of quantum memories to connect quantum repeater cells. It also enables the connection between quantum computers. In the implementation we present here, photons emitted from two co-trapped free-space coupled $^{40}$Ca$^+$ ions are converted to the telecom-C band and interfered after transmission over 440$\,$m of optical fiber (220$\,$m per arm), where a photonic Bell measurement is performed to create entanglement between the memories. With this scheme we generate an entangled $\left|\Psi^+\right\rangle$ Bell state with $\ge 68(8)\,$% fidelity, highlighting trapped $^{40}$Ca$^+$ ions as a promising quantum repeater hardware platform.

2606.12312 2026-06-11 hep-ph 新提交

Sensitivity to top-quark couplings in diboson production at lepton colliders

轻子对撞机双玻色子产生中对顶夸克耦合的灵敏度

Eugenia Celada, Víctor Miralles, Eleni Vryonidou

AI总结 研究标准模型有效场论中六维双费米子顶夸克算符对$e^+e^- \ ightarrow W^+W^-$的电弱修正,计算未来轻子对撞机(如LEP3和FCC-ee)在$t\ar{t}$阈值以下能量下的间接灵敏度,并与$ZH$产生及LEP/LHC数据比较。

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Comments
17 pages, 6 figures
AI中文摘要

我们研究了标准模型有效场论中六维双费米子顶夸克算符对$e^+e^- \ ightarrow W^+W^-$的次领头阶电弱修正。针对未来正负电子对撞机,我们计算了解析和数值结果,重点关注拟议的LEP3和FCC-ee,它们将在$t \ar{t}$产生阈值以下的质心能量运行。我们将来自$WW$产生虚修正的间接灵敏度与$ZH$产生的灵敏度以及当前LEP和LHC数据的约束进行了比较。我们表明,NLO修正可以提供对这些算符有竞争力的灵敏度。这项工作代表了在SMEFT中系统计算轻子对撞机上$W$对产生电弱修正的第一步,其影响可以在全局分析中得到适当评估。

英文摘要

We study the next-to-leading order electroweak corrections to $e^+e^- \rightarrow W^+W^-$ from dimension-six two-fermion top-quark operators in the Standard Model Effective Field Theory. We compute analytical and numerical results for future electron-positron colliders, focusing on the proposed LEP3 and FCC-ee that will operate at centre-of-mass energies below the $t \bar{t}$ production threshold. We compare the indirect sensitivity arising from virtual corrections to $WW$ production to that from $ZH$ production, and to the current constraints from LEP and LHC data. We show that NLO corrections can provide competitive sensitivity to these operators. This work represents a first step towards the systematic computation of electroweak corrections to $W$-pair production at lepton colliders in the SMEFT, whose impact can then be properly assessed in global analyses.

2606.12311 2026-06-11 cond-mat.mtrl-sci cond-mat.other 新提交

Effect of polar distortions on the anomalous Hall conductivity of altermagnetic $α$-MnTe

极性畸变对交变磁体$\alpha$-MnTe反常霍尔电导率的影响

Mathews Benny, Sahar Izadi Vishkayi, Amar Fakhredine, Chanchal K. Barman, Carmine Autieri

AI总结 研究交变磁体$\alpha$-MnTe中极性畸变对反常霍尔电导率的影响,发现表面极性畸变和弱铁磁性,并揭示晶格极化可显著调控反常霍尔电导率。

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AI中文摘要

具有沿$y$轴奈尔矢量的交变磁体$\alpha$-MnTe表现出有限的反常霍尔电导率(AHC)和沿$z$轴的弱铁磁性。正如在体材料中已证明的那样,面内奈尔矢量破坏了C$_6$对称性,留下C$_2$型磁对称性。$\alpha$-MnTe的表面破坏了C$_2$对称性,仅保留关于$x=0$平面的时间反演镜像对称性。因此,我们证明在表面上,晶体对称性破缺与奈尔矢量取向之间的相互作用导致空间群从六方P6$_3$/mmc降为正交Amm2。结果,表面不仅沿$z$轴表现出极性畸变,还沿$y$轴表现出极性畸变和弱铁磁性。为了以可访问的方式描述MnTe表面,我们简化问题并研究体材料MnTe中面内电场的影响。此外,作为掺杂离子半导体,MnTe的性质可能在外加电场下受晶格极化的影响。我们研究了本征反常霍尔效应与晶格极化之间的相互作用,表明极化效应可以显著影响AHC。由于电场破坏了反演对称性,来自晶格极化的这一贡献与非线性反常霍尔效应共存,突显了交变磁体丰富的输运现象。

英文摘要

Altermagnetic $\alpha$-MnTe with Néel vector along the $y$-axis exhibits a finite anomalous Hall conductivity (AHC) and weak ferromagnetism along the $z$-axis. As already demonstrated in the bulk, there is the breaking of the C$_6$ symmetry by the in-plane Néel vector, leaving a C$_2$-type magnetic symmetry. The surface of $\alpha$-MnTe breaks the C$_2$, leaving only a time-reversed mirror symmetry with respect to the $x=0$ plane. Therefore, we demonstrate that on the surface, the interplay between breaking of the crystal symmetry and Néel vector orientation produces a reduction of the space group from hexagonal P6$_3$/mmc to orthorhombic Amm2. As a result, the surface exhibits not only a polar distortion along the $z$-axis, but also a polar distortion and a weak ferrimagnetism along the $y$-axis. To describe the surface of MnTe in an accessible way, we simplify the problem and examine the effect of the in-plane electric field in bulk MnTe. Moreover, as a doped ionic semiconductor, the properties of MnTe can be influenced by lattice polarization under an applied electric field. We investigate the interplay between the intrinsic anomalous Hall effect and lattice polarization, showing that polarization effects can substantially affect the AHC. Since the electric field breaks inversion symmetry, this contribution from the lattice polarization coexists with the non-linear anomalous Hall effect, highlighting the rich transport phenomenology of altermagnets.

2606.12310 2026-06-11 quant-ph 新提交

Partitioned Iterative Quantum Scheduling of Satellites for Urgent Disaster Response: Case study of Wildfire

面向紧急灾害响应的卫星分区迭代量子调度:以野火为例

Lucas T. Braydwood, Taejin Park, Hirofumi Hashimoto, Zoe Gonzalez Izquierdo, Andrew Michaelis, Eleanor Rieffel, Shon Grabbe

AI总结 针对野火监测等紧急灾害响应中的卫星调度问题,提出结合迭代量子算法框架与分布式量子计算的分区调度方案,在真实数据集上验证了方法的有效性。

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11 pages, 3 figures
AI中文摘要

当今地球观测任务的标准是能够根据条件变化近乎实时地获取地表图像。例如,随着城市环境与荒野交界增多以及野火变得更加不可预测,利用卫星资源对其进行跟踪变得至关重要。这需要协调日益庞大的卫星星座,从而引发具有挑战性的计算问题。以野火检测和跟踪为背景,我们研究了专用计算和新颖计算范式在解决由此产生的卫星调度问题上的能力,为量子算法提供了有力的支持。通过考察新兴的迭代量子算法框架(该框架相比某些经典算法具有分析保证)以及分布式量子计算方法(随着实用规模问题开始用量子计算机解决,其相关性日益增强),我们使量子调度算法更接近实现。结合多个计算前沿的优势,我们开发了一种与量子算法设计相结合的分布式/并行化方案,并将这些技术应用于野火检测的真实数据集。尽管我们的量子子过程目前规模太小,无法看到显著的量子优势,但我们的结果验证了这些技术的实用性,并继续为分布式量子计算铺平道路。

英文摘要

The standard in Earth-observation tasks today is having near real-time access to surface images in response to changing conditions. For instance, as urban environments interface more with wildlands and wildfires become less predictable, their tracking with satellite resources becomes essential. This requires the coordination of increasingly large constellations of satellites, giving rise to challenging computational problems. With wildfire detection and tracking as a backdrop, we investigate the power of special purpose and novel computing paradigms to tackle the ensuing satellite scheduling problems, making a compelling case for quantum algorithms. We bring quantum scheduling algorithms closer to implementation by examining both the emerging iterative quantum algorithm framework, which comes with analytic guarantees compared to some classical algorithms, and distributed quantum computing methods whose relevance is on the rise as utility-scale problems begin to get solved with quantum computers. Drawing strength from several computing fronts, we develop a distributed/parallelization scheme in conjunction with the quantum algorithm design and apply these techniques to real-world datasets for wildfire detection. While our quantum subprocesses are currently too small to see significant quantum advantage, our results validate the utility of these techniques, and continue forging the path toward distributed quantum computing.