arXivDaily arXiv每日学术速递 周一至周五更新
全部学科分类 1938
专题追踪
2605.20454 2026-05-21 physics.soc-ph cs.SI q-bio.QM

Sparse Contextual Coupling Reshapes Diffusion Geometry in Multilayer Hypergraphs

稀疏上下文耦合重塑多层超图中的扩散几何

Hao Ding, Sanjukta Krishnagopal

AI总结 该研究提出了一种基于扩散的框架,用于分析稀疏条件特定层如何重塑多层超图中的扩散几何,通过将密集的MSigDB功能基因集层与稀疏的疾病特定DGIdb药物-基因超图耦合,发现稀疏层对扩散距离和社区结构有显著影响。

详情
AI中文摘要

许多复杂系统结合了密集的背景结构与稀疏的上下文信息。我们介绍了一种基于扩散的框架,用于分析稀疏条件特定层如何重塑多层超图中的扩散几何。每个层被表示为加权超图,层通过共享实体耦合,耦合系统上的随机游走诱导节点间的多尺度扩散距离。我们通过将密集的MSigDB功能基因集层与稀疏的疾病特定DGIdb药物-基因超图耦合,利用疾病相关的药物从DDDB和HumanNet-GSP定义外部基因权重,发现疾病特定层在耦合系统中包含不到2%的基因,但显著改变了扩散距离和社区结构。中心性分析表明,这种不成比例的影响是由于DGIdb关联的基因在MSigDB衍生的功能网络中占据重要位置。所得到的扩散衍生社区在子采样下保持稳定,并显示后验功能富集的一致性,包括神经精神疾病中的信号和神经递质类别,以及癌症相关疾病中的免疫、翻译和代谢类别。社区层面的比较进一步揭示了疾病相似性,这些相似性无法仅通过直接DGIdb基因重叠来解释,包括乳腺癌与精神分裂症的关系,这与最近的生物医学证据一致。这些结果表明,稀疏上下文层可以诱导在更高阶网络几何中的可解释非局部变化。

英文摘要

Many complex systems combine dense background structure with sparse contextual information. We introduce a diffusion-based framework for analyzing how sparse condition-specific layers reshape diffusion geometry in multilayer hypergraphs. Each layer is represented as a weighted hypergraph, layers are coupled through shared entities, and random walks on the coupled system induce multiscale diffusion distances between nodes. We apply the framework to disease-conditioned gene networks by coupling a dense MSigDB functional gene-set layer to sparse disease-specific DGIdb drug-gene hypergraphs, with disease-associated drugs selected from DDDB and HumanNet-GSP used to define external gene weights. Across Bipolar Disorder, Schizophrenia, Leukemia, and Breast Cancer, the disease-specific layer contains less than 2 percent of genes in the coupled system, yet substantially changes diffusion distances and community structure. Centrality analysis suggests that this disproportionate effect arises because DGIdb-associated genes occupy influential positions in the MSigDB-derived functional network. The resulting diffusion-derived communities are stable under subsampling and show coherent post hoc functional enrichment, including signaling and neurotransmission categories in neuropsychiatric diseases and immune, translational, and metabolic categories in cancer-associated diseases. Community-level comparisons further reveal disease similarities not reducible to direct DGIdb gene overlap, including a Breast Cancer-Schizophrenia relationship consistent with recent biomedical evidence. These results show that sparse contextual layers can induce interpretable nonlocal changes in higher-order network geometry.

2605.20453 2026-05-21 math.AG

On the Hodge and Tate conjectures for moduli spaces of curves

关于模曲线模空间的Hodge和Tate猜想

Sam Payne

AI总结 本文综述了通过Hodge和Tate猜想视角研究稳定曲线模空间的上同调近期进展,特别是广义的锥形形式如何将Hodge结构和l-adic伽罗华表示与代数循环联系起来,并讨论了开放问题和未来研究方向。

Comments 26 pages

详情
AI中文摘要

我们通过Hodge和Tate猜想的视角,综述了稳定曲线模空间的上同调近期进展,特别是它们的广义锥形形式,这些形式将Hodge结构和l-adic伽罗华表示与代数循环联系起来。我们解释了边界分层的诱导结构如何在广泛的情况下验证这些猜想,描述了来自算术的启发,并讨论了开放问题和未来研究的方向。

英文摘要

We survey recent progress on the cohomology of moduli spaces of stable curves through the lens of the Hodge and Tate conjectures, especially their generalized coniveau forms, which relate Hodge structures and l-adic Galois representations on cohomology to algebraic cycles. We explain how the inductive structure of the boundary stratification verifies these conjectures in a surprisingly wide range of cases, describe the guiding inspiration from arithmetic, and discuss open problems and directions for future research.

2605.20451 2026-05-21 math.AP

Turbulent Dynamos on Bounded Domains and Their Generalization to the Geometric Transport Equation

有界域上的湍流发电机及其对几何传输方程的推广

Giacomo Del Nin, Daniel Faraco, Sauli Lindberg, Francisco Mengual

AI总结 本文在有界域上构造了无旋速度场和磁场,解决了运动发电机方程并展示了任意磁能模式的快速增长,同时提出了统一的几何传输方程方案。

Comments 49 pages, 4 figures

详情
AI中文摘要

对于任何光滑有界域Ω⊂R³,我们构造了速度场u∈L_t^1 W^{1,p}(Ω)对于所有p<∞,以及磁场B^ε∈L_t^p C^m(Ω)对于所有p<∞和m∈N,这些场满足运动发电机方程并表现出任意磁能模式的任意快速增长,这在粘性趋近于零的极限下是均匀的。该构造基于Modena-Székelyhidi和Cheskidov-Luo的凸积分方案。主要创新点在于引入了显式势函数,使解能够局部化并避免使用反旋算子。此外,我们还提出了一种统一的几何传输方程(GTE)方案,该方案涵盖了传输方程和麦克斯韦方程。

英文摘要

For any smooth bounded domain $Ω\subset \mathbb{R}^3$, we construct a divergence-free velocity field $u \in L_t^1 W^{1,p}(Ω)$ for all $p < \infty$, and magnetic fields $B^ε\in L_t^p C^{m}(Ω)$ for all $p < \infty$ and $m\in \mathbb{N}$, that solve the kinematic dynamo equation and exhibit arbitrarily fast growth of any magnetic energy mode, uniformly in the vanishing-diffusivity limit $ε\to 0$. The construction is based on the convex integration scheme of Modena-Székelyhidi and Cheskidov-Luo. The main novelty lies in the introduction of explicit potentials, which allow the solutions to be localized and avoid the need to work with the anti-curl operator. In addition, we present a unified scheme for the geometric transport equation (GTE), which encompasses both the transport and Maxwell equations.

2605.20447 2026-05-21 quant-ph

Compact narrowband photon-pair generation by slow-light spectral engineering

通过慢光谱工程实现紧凑窄带光子对生成

Ashwith Prabhu, Elizabeth A. Goldschmidt

AI总结 本研究通过慢光谱工程在宽频带谐振腔中实现高纯度的窄带光子对生成,同时保持高 heralding 效率,为量子网络应用提供关键解决方案。

详情
AI中文摘要

高效生成带高 heralding 效率和高单光子纯度、与量子发射体、量子记忆和其他基于物质的量子比特带宽匹配的光子对,对于量子网络应用至关重要。然而,基于非线性光学的光源需要大量的谱工程来克服这些源与量子比特系统之间数量级的带宽不匹配。一个流行的解决方案是腔增强自发参量下转换(SPDC),其中腔体设定光子带宽,并同时增强SPDC的谱亮度。 bulk和自由空间配置通常需要达到与大多数量子比特系统接口所需的MHz级带宽。在可扩展的集成光子架构中复制这些配置是一个持续的挑战,因为更高的传播损耗限制了基于芯片的谐振器的大小和线宽。我们在此展示了如何通过腔内慢光介质,作为超窄滤波器,可以在宽频带谐振腔中实现高单光子纯度的窄带光子对生成,而不会影响 heralding 效率。我们证明在使用现实设计参数的掺铒薄膜铌酸锂微环中,可以轻易实现这些指标。

英文摘要

Efficiently generating photon pairs with high heralding efficiency and high single photon purity that are bandwidth matched to quantum emitters, quantum memories, and other matter-based qubits is critical for quantum networking applications. However, nonlinear optics-based sources require substantial spectral engineering to overcome the orders of magnitude bandwidth mismatch between those sources and qubit systems. A popular solution is cavity-enhanced spontaneous parametric down conversion (SPDC) where the cavity sets the photon bandwidth and simultaneously enhances the spectral brightness of the SPDC. Bulk, free-space configurations are generally required to achieve the MHz-scale bandwidths required to interface with most qubit systems. Replicating these in scalable integrated photonic architectures is an ongoing challenge due to the much higher propagation losses that limit the size and linewidth of chip-based resonators. We show here how an intra-cavity slow light medium, acting as an ultra-narrow filter, would enable narrowband photon pair generation in broadband cavities with high single photon purity and without compromising the heralding efficiency. We show that such metrics can be readily realized in erbium doped thin-film lithium niobate microrings using realistic design parameters.

2605.20446 2026-05-21 cond-mat.mtrl-sci

Evaluating Blended Refrigerants for Thermochemical Energy Storage and Circular Refrigerant Recovery using Activated Carbons

评估混合制冷剂用于热化学能量存储和循环制冷剂回收的性能 using 活性炭

H. Lucassen, A. Luna-Triguero, J. M. Vicent-Luna

AI总结 本研究通过多尺度计算方法结合分子模拟、热力学建模和突破模拟,评估了纯制冷剂及其商业混合物在六种活性炭上的吸附行为,揭示了混合制冷剂在能量存储密度和制冷剂回收中的优势。

详情
AI中文摘要

气候危机要求迅速转向可持续能源技术并提高现有能源系统的效率。基于吸附的热化学能量存储因其高能量密度和与可再生能源热源的兼容性而成为有前途的替代方案。本文研究了纯制冷剂(R32、R125、R134a 和 R600)及其商业混合物(R410A、R407F、R417A 和 R417C)在六种活性炭上的吸附行为,开发了一种多尺度计算工作流程,结合蒙特卡洛模拟、热力学建模和突破模拟,以预测吸附、存储和分离行为。该方法集成了吸附势理论(APT)、理想吸附溶液理论(IAST)以及吸附热等焓模型。此外,开发了一个内部计算框架,用于计算纯制冷剂和多组分混合物的吸附热和能量存储密度。尽管开发基于分子模拟作为基准,但该方法可以直接应用于实验研究,因为它只需要纯组分的吸附等温线作为输入来评估制冷剂混合物的性能。结果表明,制冷剂混合物由于协同吸附和更高效的分子排列,可以实现比纯组分更高的存储密度。此外,活性炭能够选择性地分离关键制冷剂组分,突显了其在可持续制冷剂回收中的潜力。总体而言,本工作提供了一个通用框架,用于合理设计和筛选下一代制冷剂混合物,用于吸附驱动的能量存储和分离应用。

英文摘要

The climate crisis demands a rapid shift to sustainable energy technologies and higher efficiency in existing energy systems. Adsorption-based thermochemical energy storage is a promising alternative due to its high energy density and compatibility with renewable heat sources. In this work, we investigate the adsorption behavior of pure refrigerants (R32, R125, R134a, and R600) and their commercial blends (R410A, R407F, R417A, and R417C) in six activated carbons for thermochemical energy storage and circular refrigerant recovery. A multiscale computational workflow combining Monte Carlo simulations, thermodynamic modeling, and breakthrough simulations is developed to predict adsorption, storage, and separation behavior from pure-component adsorption data. The methodology integrates adsorption potential theory (APT), ideal adsorbed solution theory (IAST), and models for the isosteric heat of adsorption. In addition, an in-house computational framework is developed to calculate heats of adsorption and energy storage densities for both pure refrigerants and multicomponent mixtures. Although developed using molecular simulations as a benchmark, the methodology is directly applicable to experimental studies, since it only requires adsorption isotherms of the pure components as input to evaluate the performance of refrigerant blends. The results show that refrigerant blends can achieve higher storage densities than their pure counterparts due to cooperative adsorption and more efficient molecular packing. Furthermore, the activated carbons selectively separate key refrigerant components, highlighting their potential for sustainable refrigerant recovery. Overall, this work provides a general framework for the rational design and screening of next-generation refrigerant blends for adsorption-driven energy storage and separation applications.

2605.20444 2026-05-21 math.NT math.PR

Eigenvalue Distribution of $p$-adic Random Matrices Among Algebraic Extensions, with an Analogue for $p$-adic Random Polynomials

$p$-adic 随机矩阵在代数扩张中的特征值分布,以及 $p$-adic 随机多项式的类比

Jiahe Shen

AI总结 研究 $p$-adic 随机矩阵在 $p$-adic 有理数域代数扩张中的特征值分布,通过 $p$-adic 类比于实数 Ginibre 集团的特征值计数结果,但具有不同的分布行为,同时证明最大无分支扩张 $\mathbb{Q}_p^{\mathrm{un}}$ 能捕捉几乎所有特征值,且超出该扩张的特征值数量有有限正极限。

Comments 23 pages. Comments welcome!

详情
AI中文摘要

我们研究 Haar 随机矩阵在 $\mathbb{Z}_p$ 上的特征值分布,其中 $\mathbb{Z}_p$ 是 $\mathbb{Q}_p$ 的代数扩张。我们的结果给出了 Edelman-Kostlan-Shub 对实数 Ginibre 集团的实特征值计数结果的 $p$-adic 类比,但具有不同的分布行为:虽然实特征值在实 Ginibre 集团中仅占微小比例,$p$-adic 特征值则在可能的扩展次数中渐近均匀分布。我们还证明最大无分支扩张 $\mathbb{Q}_p^{\mathrm{un}}$ 能捕捉所有但至多有限期望数量的特征值,且超出 $\mathbb{Q}_p^{\mathrm{un}}$ 的特征值数量的期望有有限正极限,且具有显式上界。证明使用了作者与 Van Peski 共同之前的相关函数公式(arXiv:2601.06283),以及在变化有限扩展中的统一估计。我们还证明了随机 Haar 多项式根的类似结果,使用了 Caruso 的相关函数公式(arXiv:2110.03942)。这些多项式结果是 Edelman-Kostlan 实根计数结果的 $p$-adic 类比,但行为不同于实数情况。

英文摘要

We study the distribution of eigenvalues of Haar-random matrices over $\mathbb{Z}_p$ among algebraic extensions of $\mathbb{Q}_p$. Our results give $p$-adic analogues of the real-eigenvalue counting results of Edelman-Kostlan-Shub for the real Ginibre ensemble, but with a different degree behavior: while real eigenvalues form only a vanishing proportion in the real Ginibre ensemble, $p$-adic eigenvalues are asymptotically evenly distributed among possible extension degrees. We also show that the maximal unramified extension $\mathbb{Q}_p^{\mathrm{un}}$ captures all but a bounded expected number of eigenvalues, and that the expected number of eigenvalues outside $\mathbb{Q}_p^{\mathrm{un}}$ has a finite positive limit with an explicit upper bound. The proof uses correlation function formulas from the author's previous joint work with Van Peski (arXiv:2601.06283), together with uniform estimates over varying finite extensions. We also prove analogous results for roots of random Haar polynomials over $\mathbb{Z}_p$, using the correlation function formulas of Caruso (arXiv:2110.03942). These polynomial results are $p$-adic analogues of the real-root counting results of Edelman-Kostlan, again with behavior different from the real setting.

2605.20438 2026-05-21 cs.HC

Closing the Motivation Gap: Incentives Enhance Visual Misinformation Discernment and Verification

弥合动机差距:激励提升视觉虚假信息辨识与验证

Sijia Qian, Cuihua Shen, Jingwen Zhang, Magdalena Wojcieszak

AI总结 本研究探讨了在数字媒体素养干预中引入不同激励机制和类型是否能提高视觉虚假信息的辨识和图像验证行为,发现任务型激励特别是金钱激励最有效激发图像验证行为,而结果型激励更有效维持辨识准确性。

详情
AI中文摘要

廉价假象,或以误导性或无关情境呈现的真图像,已成为日益突出的视觉虚假信息形式。尽管媒体素养干预可以增强个体识别此类内容的能力,但动机障碍往往阻碍图像验证的采用。本研究探讨了在数字媒体素养干预中引入不同激励机制和类型是否能提高视觉虚假信息辨识和图像验证行为,立即和长期。我们在一个专业设计的社会媒体平台上进行了一项预注册的两波被试间在线实验(N=1,421)。该研究采用2(激励类型:象征性vs.金钱)x2(激励机制:任务型vs.结果型)的因子设计,并有额外的控制组。结果显示,任务型激励,特别是金钱激励,最有效激发图像验证行为,即反向图像搜索,并提升短期辨识能力,而结果型激励更有效维持辨识准确性。这些发现表明,激励机制和类型在塑造媒体素养干预短期和长期有效性方面起着关键作用,突显了多阶段激励策略在对抗数字环境中视觉虚假信息的价值。

英文摘要

Cheapfakes, or real images presented misleadingly or in unrelated contexts, are an increasingly prominent form of visual misinformation. While media literacy interventions can enhance individuals' ability to detect such content, motivational barriers often hinder the adoption of image verification. This study examines whether incorporating different mechanisms and types of incentives into a digital media literacy intervention improves visual misinformation discernment and image verification behavior, both immediately and over time. We conducted a pre-registered two-wave between-subjects online experiment (N = 1,421) on a professionally designed social media platform. The study used a 2 (Incentive Type: symbolic vs. monetary) x 2 (Incentive Mechanism: task- vs. result-based) factorial design with additional control groups. Results show that task-based incentives, particularly monetary ones, were most effective at initiating image verification behaviors, namely reverse image search, and boosting short-term discernment, whereas result-based incentives were more effective in sustaining discernment accuracy. These findings suggest that both the mechanism and the type of incentives play a critical role in shaping the short- and long-term effectiveness of media literacy interventions, highlighting the value of multi-phased incentive strategies for combating visual misinformation in digital environments.

2605.20437 2026-05-21 cond-mat.supr-con cond-mat.mtrl-sci

Superconducting PdTe Thin Film Via Topotactic Transformation, Toward Topological Superconductors

通过拓扑转化制备超导PdTe薄膜,迈向拓扑超导体

Hee Taek Yi, Min Ge, Renjie Xie, Colby J. Stoddard, David H. Yi, Xiaoyu Yuan, Xiong Yao, Seongshik Oh

AI总结 本研究通过分子束 epitaxy 制备出高质量超导PdTe薄膜,展示了其与体材料相似的超导特性,为拓扑超导体和Majorana物理提供了新平台。

Comments 14 pages, 4 figures, accepted for publication in ACS Applied Nano Materials

详情
AI中文摘要

拓扑超导体(TSCs) hosting Majorana零模(MZMs)提供了一条实现容错量子计算的途径。PdTe因其拓扑表面态和合理的超导临界温度(约4.5 K)成为有前途的TSC候选材料。然而,生长具有体材料超导特性的PdTe薄膜一直具有挑战性。在此,我们展示通过分子束 epitaxy(MBE)生长出高质量的超导PdTe薄膜。这些薄膜表现出尖锐的超导转变(T_onset = 4.43 K,转变宽度为0.06 K),与体材料相当。这通过在Te不足条件下在PdTe_2缓冲层上生长Pd,从而通过拓扑转化转变为PdTe相实现。结构和输运分析确认了PdTe的NiAs型结构,以及其二维超导行为和优异的空气稳定性。这些发现表明,MBE生长的PdTe薄膜及其异质结构是拓扑超导性和Majorana物理的有前途的平台。

英文摘要

Topological superconductors (TSCs) hosting Majorana zero modes (MZMs) offer a pathway to fault-tolerant quantum computation. PdTe is a promising TSC candidate due to its topological surface states and a reasonable superconducting critical temperature of ~4.5 K. However, it has been challenging to grow PdTe thin films with bulk-like superconducting properties. Here, we show that high-quality, superconducting PdTe thin films can be grown using molecular beam epitaxy (MBE). The films exhibit a sharp superconducting transition (T_onset = 4.43 K with transition width of 0.06 K), comparable to that of bulk crystals. This was made possible via a topotactic transformation from a PdTe_2 buffer layer to a PdTe phase by growing Pd on top under Te-deficient conditions. Structural and transport analyses confirm the NiAs-type structure of PdTe, as well as its two-dimensional superconducting behavior and excellent air stability. These findings suggest that the MBE-grown PdTe films and their heterostructures are a promising platform for topological superconductivity and Majorana physics.

2605.20430 2026-05-21 cond-mat.mes-hall cond-mat.mtrl-sci

Excitation-Energy-Selective Control of Hot-Carrier Cooling via a Resonant Optical-Phonon Bottleneck in Graphene

通过石墨烯中的共振光学声子瓶颈实现激发能选择性控制的热点载流子冷却

Sachin Sharm, Elliott Walker, Rachael Myers-Ward, Jenifer Hajzus, Yijing Liu, Paola Barbara, Ioannis Chatzakis

AI总结 研究通过石墨烯中的共振光学声子瓶颈实现了对热点载流子冷却的激发能选择性控制,揭示了载流子弛豫时间与激发光子能量之间的非单调依赖关系,并展示了通过增强光学声子寿命来抑制能量向晶格转移的机制。

Comments 37 pages, 5 figures, under review

详情
AI中文摘要

理解并控制石墨烯中的热点载流子弛豫对于推进超快光电和太赫兹技术至关重要。在这里,我们利用中红外泵脉冲(0.22-0.73 eV)和太赫兹探测脉冲研究单层和双层石墨烯中的载流子冷却动力学。我们发现载流子弛豫时间对激发光子能量呈现显著、可重复且非单调的依赖关系。值得注意的是,在狭窄的光谱窗口(0.42到0.48 eV)内,载流子寿命比在其他能量下的几皮秒级冷却增加了数量级。我们证明这种异常的减慢源于光学声子寿命的共振增强,导致热点光学声子的积累和再吸收,从而抑制能量向晶格的转移。所有观察到的行为均能通过统一的载流子-声子能量平衡框架来捕捉,其中激发能依赖的有效的光学声子衰变路径变化决定了冷却动力学。这些发现展示了石墨烯中热点载流子弛豫的激发能选择性控制,并提供了关于非平衡载流子-声子相互作用在光学声子瓶颈附近的新见解。

英文摘要

Understanding and controlling hot-carrier relaxation in graphene is crucial for advancing ultrafast optoelectronic and terahertz technologies. Here, we investigate carrier cooling dynamics in monolayer and bilayer graphene using mid-infrared pump pulses (0.22-0.73 eV) and terahertz probe pulses. We uncover a pronounced, reproducible, and non-monotonic dependence of the carrier relaxation time on excitation photon energy. Remarkably, within a narrow spectral window (0.42 to 0.48 eV), the carrier lifetime increases by an order of magnitude compared to a few picosecond-scale cooling observed at other energies. We show that this anomalous slowdown originates from a resonant enhancement of the optical-phonon lifetime, causing accumulation and reabsorption of hot optical phonons that suppress energy transfer to the lattice. All observed behaviors are captured within a unified carrier-phonon energy-balance framework, where excitation-energy-dependent variations of the effective optical-phonon decay pathway govern the cooling dynamics. These findings demonstrate excitation-energy-selective control of hot-carrier relaxation in graphene and provide new insight into non-equilibrium carrier-phonon interactions near the optical-phonon bottleneck.

2605.20429 2026-05-21 stat.AP

Design and Validation of a Grid-based Home Detection via Stay-Time (GHOST) Software for Mobile Location Data

基于停留时间的网格化家庭检测(GHOST)软件的设计与验证:用于移动定位数据

Alessandra Recalde, Mustafa Sameen, Xiaojian Zhang, Xilei Zhao

AI总结 本研究提出了一种基于网格和停留时间的家庭检测算法GHOST,通过定制的空间和时间过滤器识别最频繁访问的夜间或周末白天网格单元,以推断代理家庭位置,并在大规模数据集上验证其在噪声数据中的鲁棒性。

详情
AI中文摘要

从移动设备生成的GPS数据中准确检测家庭位置是人类移动性研究的基础步骤,对交通规划、公共卫生和应急响应有重要影响。然而,现有的家庭检测算法在处理真实世界中的噪声数据时往往结果不可靠,并且由于缺乏地面真实基准而难以验证。为解决这些限制,本研究提出了GHOST算法的设计与验证,作为开源的Python包实现。该算法通过识别基于可定制空间和时间过滤器的最频繁访问的夜间或周末白天网格单元来推断代理家庭位置。为了验证其性能,我们使用包含超过155,000次行程的大型波士顿步行数据集,该数据集来自波士顿都会区的377名参与者,以测试其对噪声数据的鲁棒性。此外,我们还收集了来自美国不同地区的10名志愿者的地面真实数据,包括佛罗里达、密西西比和科罗拉多,以及他们自报的家庭坐标,以评估GHOST在多样化的移动模式和采样条件下的表现。我们比较了GHOST的准确性与五种已建立的家庭检测算法:All-time clustering方法、Stay-point方法、DBSCAN、K-MEANS++和SciKit-Mobility Home Detection在多种参数设置下的表现。结果表明,GHOST在准确性和鲁棒性方面均优于所有算法,最佳配置下的平均误差低至22.3米。我们的发现突显了该算法的高准确性和灵活性,其中网格大小是验证过程中最影响性的参数,展示了该算法在真实世界移动定位数据分析中的潜力。

英文摘要

Accurately detecting home locations from GPS data generated by mobile devices is a foundational step in human mobility research, with significant implications for transportation planning, public health, and emergency response. However, existing home detection algorithms often produce unreliable results for noisy real-world data and are barely validated due to a lack of ground-truth benchmarks. To tackle these limitations, this study presents the development and validation of a Grid-based home detection via Stay-Time (GHOST) algorithm, implemented as an open-source Python package. The algorithm infers proxy home locations by identifying the most frequently visited nighttime or weekend daytime grid cells based on customizable spatial and temporal filters. To validate its performance, we use the large-scale BostonWalks dataset, which includes over 155,000 trips from 377 participants in the Boston metropolitan area, to test robustness to noisy data. Additionally, we collected a ground-truth dataset for ten volunteers across different regions in the U.S., including Florida, Mississippi, and Colorado, along with their self-reported home coordinates, to evaluate GHOST across diverse mobility patterns and sampling conditions. We compared GHOST accuracy to that of 5 well-established home detection algorithms: All-time clustering method, Stay-point method, DBSCAN, K-MEANS++, and SciKit-Mobility Home Detection, across multiple parameter settings. Results show that GHOST outperforms all algorithms in accuracy and robustness, with average errors as low as 22.3 meters under optimal configurations. Our findings highlight the high accuracy and flexibility of our algorithm, with grid size being the most influential parameter during validation, demonstrating the potential of this algorithm for real-world mobile location data analysis.

2605.20428 2026-05-21 cond-mat.mes-hall cond-mat.mtrl-sci

Fröhlich-type Polarons in Isotopically Enriched Hexagonal Boron Nitride

六方氮化硼中同位素富集的弗罗赫利希型极子

Ioannis Chatzakis, Timur Abdilov, Elliot Walker, Jaime Freitas, Song Liu, James H. Edgar

AI总结 研究通过低温阴极发光揭示了同位素富集六方氮化硼中的弗罗赫利希型激子-声子耦合,确定了间接激子能级及其纵向声子副本,并提取出弗罗赫利希耦合常数和更大的激子结合能,为调控其声子极子和量子光学性质提供了基础。

Comments 34 pages, 6 figures, under review (supporting information is not included)

详情
AI中文摘要

激子-声子相互作用在定义六方氮化硼(hBN)的光学响应中起着核心作用,但其定量确定仍不完整。在这里,我们利用低温阴极发光揭示了硼-10富集的hBN中的弗罗赫利希型激子-声子耦合。我们解析了间接激子5.95±0.02 eV及其纵向声子副本,该副本偏离184±56 meV,从而提取出弗罗赫利希耦合常数α=0.159和更大的激子结合能161 meV,比自然丰度hBN之前报告的值更大,这归因于同位素富集。推断的极子半径超过晶格常数,表明存在大极子行为。我们推导出激子散射时间约为97 fs,对应于均匀线宽约为6.76 meV。我们进一步获得了极子结合能约为48 meV和有效质量1.045 m₀。这些结果为同位素工程hBN中的激子-声子耦合提供了直接定量表征,并建立了调控其声子极子和量子光学性质的基础。

英文摘要

Exciton-phonon interactions play a central role in defining the optical response of hexagonal boron nitride (hBN), yet their quantitative determination has remained incomplete. Here, we reveal the Fröhlich-type exciton-phonon coupling in boron-10-enriched hBN using low-temperature cathodoluminescence. We resolve the indirect exciton 5.95$\pm$0.02 eV together with its longitudinal optical (LO) phonon replica detuned by 184$\pm$56 meV, enabling the extraction of a Fröhlich coupling constant $α$=0.159 and a larger exciton binding energy of 161 meV, larger than previously reported values for natural-abundance hBN, which is attributed to isotope enrichment. The inferred polaron radius exceeds the lattice constant, indicating large-polaron behavior. We deduced an exciton scattering time ~of 97 fs, corresponding to a homogeneous linewidth of ~6.76 meV. We further obtain a polaron binding energy of ~48 meV and an effective mass of 1.045 $m_0$. These results provide a direct quantitative characterization of exciton-phonon coupling in isotopically engineered hBN and establish a foundation for tailoring its phonon-polaritonic and quantum-optical properties.

2605.20426 2026-05-21 math.AP

Pointwise bounds and obstructions to blowup for the Landau and Boltzmann equations

关于Landau和Boltzmann方程的点界及爆炸障碍

William Golding, Christopher Henderson, Luis Silvestre

AI总结 本文基于Landau和Boltzmann方程的新先验估计,建立了不依赖流体量界条件的持续性准则,并展示了流体方程中的奇点与Boltzmann和Landau方程的不相容性。

Comments 23 pages, 1 figure

详情
AI中文摘要

我们建立了空间非均匀Landau和Boltzmann方程解的新先验估计。作为结果,我们证明了一个基于加权$ L^\infty $-范数的新的持续性准则,而无需对流体量进行界约束。这从不同的视角补充了现有条件正则性结果。随后,我们展示流体方程中的奇点与Boltzmann和Landau方程 largely 不相容。更具体地说,我们基本上排除了将3D欧拉方程中的奇点提升到动能方程物理范围的机制,这是广泛预期的奇点形成机制。在一般考虑下,对于软势,这种机制基本上被排除,而对于硬势,情况更为复杂:无法通过标准流体ansatz使用已知的内爆解来产生爆破。

英文摘要

We establish a new a priori estimate on solutions to the space-inhomogeneous Landau and Boltzmann equations. As a consequence, we prove a new continuation criterion, based on a weighted $L^\infty$-norm, without requiring bounds on the hydrodynamic quantities. This complements existing conditional regularity results from a rather different perspective. Consequently, we show that the singularities present in the fluid equations are largely incompatible with the Boltzmann and Landau equations. More precisely, we largely rule out ``lifting a singularity'' from the 3D Euler equations to the physical range of kinetic equations, a widely expected mechanism for singularity formation. Under general considerations, this mechanism is essentially excluded for soft potentials, whereas for hard potentials the situation is more nuanced: one cannot produce blowup through the standard hydrodynamic ansatz using known imploding solutions to the Euler equations.

2605.20424 2026-05-21 physics.optics

Room-temperature THz photon detection via nonlinear upconversion with 2% full-system efficiency

室温下通过非线性上转换实现太赫兹光子检测,系统效率为2%

Aswin Vishnuradhan, Wei Cui, Hesam Heydarian, Eeswar Kumar Yalavarthi, Nicolas Couture, Alain Villeneuve, Angela Gamouras, Jean-Michel Ménard

AI总结 本研究通过有机晶体N-苯基-2-甲基-4-硝基苯胺(BNA)中的非线性上转换,在室温下实现了高效太赫兹检测,解决了从1到7.5 THz频率的检测问题,系统整体检测效率达到2%。

Comments 7 pages, 4 figures

详情
AI中文摘要

灵敏检测太赫兹(THz)辐射对于光谱学、先进无线通信和新兴量子技术的实现至关重要。然而,太赫兹范围内的固有低光子能量与热背景辐射相结合,通常会限制在环境温度下工作的探测器性能。在这里,我们展示了基于有机晶体N-苯基-2-甲基-4-硝基苯胺(BNA)中的非线性上转换的高效室温太赫兹检测,能够检测从1到7.5 THz的频率。该系统包含光谱滤波器和单光子计数器,实现了总检测效率为2%的和频生成光子。这使得能够检测一个包含平均每个脉冲少于0.04个光子的50000个太赫兹脉冲,信噪比为1。在更高的通量下,当约60个光子每脉冲撞击BNA晶体时,每脉冲的检测概率达到50%。在考虑了装置中的损失机制后,BNA中的非线性太赫兹到近红外转换效率超过75%。这些结果证明了在环境条件下通过非线性晶体中的上转换实现单光子水平太赫兹检测的量子实验的可行性。

英文摘要

Sensitive detection of terahertz (THz) radiation is fundamental to progress in spectroscopy, advanced wireless communication, and the realization of emerging quantum technologies. However, the intrinsically low photon energies in the THz range combined with thermal background radiation tend to constrain detector performance when operating at ambient temperatures. Here, we demonstrate efficient room-temperature THz detection based on nonlinear upconversion in the organic crystal N-benzyl-2-methyl-4-nitroaniline (BNA) to resolve frequencies from 1 to 7.5 THz. The system encompassing spectral filters and a single-photon counter achieves an overall detection efficiency of 2% for sum-frequency generated photons. This enables the detection of a train of 50 000 terahertz pulses carrying, on average, fewer than 0.04 photons per pulse, with a signal-to-noise ratio of unity. At a higher flux, when ~60 photons per pulse impinge on the BNA crystal, the per-pulse detection probability reaches 50%. After accounting for loss mechanisms in the setup, the nonlinear THz-to-near-infrared conversion efficiency in BNA exceeds 75%. These results demonstrate the feasibility of quantum experiments relying on single-photon-level THz detection via upconversion in nonlinear crystals in ambient conditions.

2605.20421 2026-05-21 cs.FL cs.LO

Intersecting Dense Automata

相交的密集自动机

Dmitry Chistikov, Neha Rino

AI总结 本文提出了一种更高效的NFA交集空性判定算法,通过改进的构造方法减少了状态转移的数量,从而在最坏情况下提高了效率。

Comments 24 pages, 7 figures

详情
AI中文摘要

我们观察到,经典的Cartesian积构造用于确定非确定有限自动机(NFA)语言的交集在最坏情况下并非最优,如果自动机有大量转移。对于固定的字母表,两个NFA的乘积可能有Θ(m²)个转移,如果这些NFA最多有n个状态和m个转移每个。我们描述了替代构造,具有O(mn)个转移:或者对于k个NFA的交集,具有O(mn^{k-1})个转移(对于固定的k≥2和字母表Σ)。这给出了一个更快的决定NFA交集空性的算法。新的算法是最佳的,除非存在突破性的组合算法来检测无向图中的(k+1)- clique。这还导致了NFA交集空性的更有效的认证方案。

英文摘要

We observe that the classical Cartesian product construction for the intersection of (languages of) nondeterministic finite automata (NFA) is non-optimal in the worst case, if the automata have many transitions. For a fixed alphabet, the product of two NFA may have $Θ(m^2)$ transitions if these NFA have at most $n$ states and $m$ transitions each. We describe alternative constructions with $O(m n)$ transitions: or $O(m n^{k-1})$ for the intersection of $k$ NFA (for fixed $k \ge 2$ and alphabet $Σ$). This gives a faster algorithm for deciding NFA intersection emptiness. The new algorithm is optimal, unless there exists a breakthrough combinatorial algorithm for detecting $(k+1)$-cliques in undirected graphs. This also leads to a more efficient certification scheme for NFA intersection emptiness.

2605.20420 2026-05-21 cond-mat.mes-hall physics.app-ph

An AI-driven robotic system for two-dimensional hetero-assemblies

基于人工智能的二维异质组装机器人系统

Xiaoxi Li, Jinkun He, Haojie Liu, Xipeng Liu, Zewen Wu, Jing Li, Kai Zhao, Shan Li, Xingdan Sun, Xiaoxue Fan, Zhiren Xiong, Xingguang Wu, Xuanzhe Sha, Zhili Lin, Caixia Yang, Luosha Han, Jie Xu, Woye Pei, Kaining Yang, Jing Zhang, Xiaolong Feng, Tongyao Zhang, Zhu Liang, Kenji Watanabe, Takashi Taniguchi, Ming Tian, Neng Wan, Jing Zhang, Jianming Lu, Wenjing Hong, Zheng Vitto Han

AI总结 本文提出了一种基于人工智能的机器人系统,用于高效自动化制造二维范德瓦尔异质结构,通过强化学习提升性能,展示了扭曲双层石墨烯的非常规超导性。

Comments 18 pages, 11 figures

详情
AI中文摘要

按需堆叠的纳米材料,如旋转组装的二维(2D)范德瓦尔(vdW)层状化合物,为量子模拟和探索奇异电子相提供了灵活的平台。然而,目前这些纳米组装仍主要受限于低效和手动操作的过程,限制了其探测新兴物理现象的潜力。该领域迫切需要高精度、自动组装技术,特别是用于大规模制造二维扭态异质结构。本文提出了一种专门用于制造范德瓦尔堆叠的智能自动化系统,遵循最先进的干法转移剥离二维材料的协议。该系统进一步利用每个自动堆叠过程生成的元数据进行强化学习,从而持续提升其性能。作为具体演示,我们制造了扭曲双层石墨烯(TBLG)——以其具有挑战性的制备而闻名,并展示了其在魔角附近出现的非常规超导性。我们的工作可能为低维纳米材料的高通量制造铺平道路,包括扭态异质结构,其中数据挖掘和人工智能的结合可以加速新物理现象的发现。

英文摘要

Nanomaterials stacked on-demand, such as rotationally assembled two-dimensional (2D) van der Waals (vdW) layered compounds, provides a versatile platform for quantum simulation and the exploration of exotic electronic phases. Currently, however, such nanoassemblies remain largely confined to inefficiency, manually operated process, limiting their potential for probing emergent physical phenomena. There is a pressing need in the field for high-precision, automated assembling techniques, especially for the scalable fabrication of 2D twistronic heterostructures. Here, we present an intelligent automation system dedicated to the fabrication of van der Waals stacks, following the state-of-the-art protocol for dry transfer of exfoliated 2D materials. The system further employs metadata generated from each automated stacking procedure to perform reinforcement learning, thereby continuously bettering its performances. As a concrete demonstration, we fabricate twisted bilayer graphene (TBLG) -- known for its challenging preparation -- and exhibit its unconventional superconductivity near the magic angle. Our work may pave the way for high-throughput fabrication of low-dimensional nanomaterials including twistronic heterostructures, where integrating data mining and artificial intelligence can accelerate the discovery of novel physical phenomena.

2605.20419 2026-05-21 math.GR math.MG

Polynomial hyperbolicity and products of free groups

多项式超几何性与自由群的积

Anthony Genevois

AI总结 本文研究了局部有限图在某种条件下成为多项式超几何空间的性质,证明了在紧致特殊群中,不含自由群F₂×F₂作为子群等价于是线性多项式超几何的,且包含F₂×F₂作为子群在紧致特殊群中是准等距不变的。

Comments 33 pages, 11 figures. Comments are welcome!

详情
AI中文摘要

在本文中,我们定义一个局部有限图X为η-多项式超几何如果存在一个Lipschitz映射φ: X → Z到某个超几何空间Z,满足以下条件:存在C ≥ 0使得对于所有p, q ∈ X,R₁, R₂ ≥ 0,有|B(p, R₁) ∩ φ⁻¹(B(q, R₂))| ≤ (C R₁)^(η(C R₂))。我们主要结果是,在紧致特殊群中,成为lin-多项式超几何等价于不包含F₂×F₂作为子群。因此,包含F₂×F₂作为子群在紧致特殊群中是准等距不变的。

英文摘要

In this article, we define a locally finite graph $X$ as $η$-polynomially hyperbolic if there exists a Lipschitz map $φ: X \to Z$ to some hyperbolic space $Z$ satisfying the following condition: there exists $C \geq 0$ such that $$|B(p,R_1) \cap φ^{-1} (B(q,R_2))| \leq (C R_1)^{η(C R_2)} \text{ for all } p,q \in X, R_1,R_2 \geq 0.$$ The picture to keep in mind is that coarse fibres of $φ$ have polynomial growth with a degree coarsely controlled by $η$ as the thickness of the fibres grows. The map $η$ quantifies how brutal we have to be in order to turn $X$ into a hyperbolic space. Our main result is that, among cocompact special groups, being $\mathrm{lin}$-polynomially hyperbolic amounts not to contain $\mathbb{F}_2 \times \mathbb{F}_2$ as a subgroup. Consequently, containing $\mathbb{F}_2 \times \mathbb{F}_2$ as a subgroup turns out to be quasi-isometric invariant for cocompact special groups.

2605.20417 2026-05-21 hep-lat hep-ph nucl-th quant-ph

Quantum Simulation of Gauge Theories for Particle and Nuclear Physics

粒子与核物理中的规范理论量子模拟

Zohreh Davoudi

AI总结 本文探讨了利用量子计算进行规范理论模拟在粒子和核物理中的应用,介绍了该方法的核心方法、主要贡献及当前进展。

Comments 16 pages, 10 figures. Contribution to Proceedings of the 42nd International Symposium on Lattice Field Theory (LATTICE2025)

详情
AI中文摘要

格点场论,加上其算法和硬件生态系统,一直是计算粒子和核物理的前沿。它继续在强子能谱、结构、衰变和反应方面取得令人印象深刻的结果。然而,这种积极的行动在处理涉及密集物质和一般动态现象的问题时却显得不足。原因在于此类问题需要随系统尺寸呈指数级增长的计算时间和空间。量子模拟,通过量子计算算法和硬件技术,提供了一种前进的途径,因为它提供了比其低效的经典对应物多项式高效的算法。格点规范理论家已经开展了多管齐下的计划,以利用这些新可能性,并稳步推进了理论、算法和硬件实现以及协同设计。在本次演讲中,我将阐述量子计算格点场论计划的动机;介绍该计划预期解决的问题和所涉及的策略;报告最近的进展;并最后提到未来的挑战和机遇。

英文摘要

Lattice field theory, along with its algorithmic and hardware ecosystems, has been at the forefront of computational particle and nuclear physics. It continues to deliver impressive results on the hadronic spectrum, structure, decays, and reactions. Yet, this vigorous campaign has fallen short in addressing a range of problems involving dense matter and general dynamical phenomena. The reason is that such problems require an exponential scaling of computing time and space in system size. Quantum simulation, enabled by quantum-computing algorithms and hardware technology, promises a way forward by offering several polynomially efficient algorithms compared with their inefficient classical counterparts. Lattice gauge theorists have engaged in a multi-pronged program to leverage such new possibilities, and have steadily advanced the state of theory, algorithm, and hardware implementations and co-design. In this talk, I motivate the quantum-computational lattice-field-theory program; introduce the questions such a program is expected to address and the strategies it involves; report on recent progress; and end with a note on challenges and opportunities ahead.

2605.20415 2026-05-21 hep-th cond-mat.mes-hall cond-mat.supr-con gr-qc

The dual Ginzburg-Landau theory for a holographic superfluid/superconductor: Critical dynamics

双Ginzburg-Landau理论用于全息超流/超导体:临界动力学

Makoto Natsuume

AI总结 本文研究全息超流/超导体在临界动力学中的双Ginzburg-Landau理论,通过精确求解得到模型F方程的系数,揭示其临界行为。

Comments 22 pages

详情
AI中文摘要

全息超流/超导体是AdS/CFT对偶中研究最多系统之一。在低能、长波长极限下,它们应由Ginzburg-Landau理论描述。对于临界动力学,预期它们属于“模型F” universality 类。我们考虑在探测极限下5维全息超导体。对于全息超导体,我们施加边界Maxwell方程以使边界Maxwell场动力学。我们识别出双模型F方程,其中的数值系数被精确求得。

英文摘要

Holographic superfluids/superconductors are one of the most studied systems in the AdS/CFT duality. In the low-energy, in the long-wavelength limit, they should be described by a Ginzburg-Landau theory. For critical dynamics, one expects that they belong to "model F" universality class. We consider a bulk 5-dimensional holographic superfluid/superconductor in the probe limit. For the holographic superconductor, we impose the boundary Maxwell equation to make the boundary Maxwell field dynamical. We identify the dual model F equations where numerical coefficients are obtained exactly.

2605.20412 2026-05-21 math.FA math.CA math.MG

Brascamp--Lieb inequalities for fractal dimensions

关于分形维度的Brascamp--Lieb不等式

Jonathan M. Fraser

AI总结 本文利用泛函分析中的Brascamp--Lieb不等式,证明了关于分形集的上盒维数、包络维数和Assouad维数的新不等式,这些不等式以某些投影的维数为条件。与Hausdorff和下盒维数不同,类似不等式不成立。作者将这些分形Brascamp--Lieb不等式应用于正交投影的例外集估计,并为某些受限和集提供精确的维数估计,同时通过非线性Brascamp--Lieb不等式建立了类似的非线性不等式。

Comments 18 pages

详情
AI中文摘要

我们利用泛函分析中的Brascamp--Lieb不等式,证明了关于分形集的上盒维数、包络维数和Assouad维数的新不等式,这些不等式以某些投影的维数为条件。与Hausdorff和下盒维数不同,类似不等式不成立。我们应用这些分形Brascamp--Lieb不等式来建立正交投影的例外集估计,并为某些受限和集提供精确的维数估计。我们还通过非线性Brascamp--Lieb不等式建立了类似的非线性不等式。

英文摘要

We use the Brascamp--Lieb inequality from functional analysis to prove novel inequalities for the upper box, packing, and Assouad dimensions of fractal sets in terms of the dimensions of certain projections. Analogous inequalities do not hold for Hausdorff or lower box dimensions. We apply these fractal Brascamp--Lieb inequalities to establish new exceptional set estimates for orthogonal projections and to provide sharp dimension estimates for certain constrained sumsets. We also establish analogous nonlinear inequalities via the nonlinear Brascamp--Lieb inequality.

2605.20411 2026-05-21 eess.SY cs.SY

Max-Entropy Moment Filtering for Stochastic Hybrid Systems

最大熵矩滤波器用于随机混合系统

Kaito Iwasaki, Tejaswi K. C., Anthony Bloch, Maani Ghaffari, Taeyoung Lee

AI总结 本文提出了一种混合扩展的最大熵矩卡尔曼滤波器,用于从部分统计信息中进行滤波,通过传播有限的矩并通过随机混合动态重构信念,关键步骤是基于Dynkin公式推导出的矩传播规则,能够有效处理边界诱导的概率流,从而在不求解底层混合PDE的情况下获得可处理的矩动力学。

Comments 8 pages, 6 figures

详情
AI中文摘要

随机混合系统结合了连续时间随机动态与离散重置事件,产生本质上非高斯且通常多模态的不确定性。一致的传播定律还必须考虑边界诱导的概率流穿过守卫集,使得直接通过混合福克-普朗克方程进行密度传播变得昂贵。我们开发了一种混合扩展的最大熵矩卡尔曼滤波器(MEM-KF),通过传播有限的矩并通过随机混合动态重构信念。关键步骤是基于Dynkin公式推导出的矩传播规则,其中重置效应表现为守卫集上的边界流校正。这产生了可处理的矩动力学,而无需求解底层混合PDE。在随机弹跳球示例中,所提出的方法通过校正的矩方程捕捉重置诱导的非高斯性,同时保留MEM-KF的基于优化的最大熵表示。

英文摘要

Stochastic hybrid systems combine continuous-time stochastic dynamics with discrete reset events, producing intrinsically non-Gaussian and often multimodal uncertainty. A consistent propagation law must also account for boundary-induced probability flux across guard sets, making direct density propagation through hybrid Fokker-Planck equations expensive. We develop a hybrid extension of the Max-Entropy Moment Kalman Filter (MEM-KF) that performs filtering from partial statistical information by propagating a finite collection of moments through stochastic hybrid dynamics and reconstructing beliefs using moment-constrained maximum-entropy distributions. The key step is a moment propagation rule derived from Dynkin's formula with a jump-sum, in which reset effects appear as a boundary-flux correction over the guard set. This yields tractable moment dynamics without solving the underlying hybrid PDE. In a stochastic bouncing-ball example, the proposed method captures reset-induced non-Gaussianity through corrected moment equations while retaining the MEM-KF's optimization-based maximum-entropy representation.

2605.20409 2026-05-21 math.CO

Higher cosystoles of matroids

Matroid 的更高余系

James Dylan Douthitt, Elana Israel, Lee Kennard

AI总结 本文定义了一个名为三余系的 matroid 不变量,与加权 matroid 的更高 cogirth 概念相关,并在 rank 最多为六的 regular matroid 类中证明了其最优上界。为此,作者展示了它在 matroid 扩展下是递增的,并对每个 rank 最多为六的最大简单 regular matroid 进行了估计。

详情
AI中文摘要

我们定义了一个名为三余系的 matroid 不变量,与加权 matroid 的更高 cogirth 概念相关,并在 rank 最多为六的 regular matroid 类中证明了其最优上界。为此,我们展示了它在 matroid 扩展下是递增的,并对每个 rank 最多为六的最大简单 regular matroid 进行了估计。

英文摘要

We define a matroid invariant called the three-cosystole that is related to higher notions of cogirth for weighted matroids, and we prove an optimal upper bound for it in the class of regular matroids of rank at most six. To accomplish this, we show that it is increasing under matroid extensions and then estimate it for each of the maximal simple regular matroids of rank at most six.

2605.20406 2026-05-21 physics.app-ph

High Performance TiO2 Ferroelectric Field Effect Transistors with HfZrO2 for Neuromorphic Computing

高性能TiO2铁电场效应晶体管用于神经形态计算

Chandan Samanta, Elia Palmese, Ziyu Ouyang, Tuofu Zhama, Robinson Pino, Yuping Zeng

AI总结 本文研究了采用HfZrO2铁电介质层和底部栅极拓扑结构的TiO2铁电场效应晶体管,通过改变铁电栅极堆叠厚度和源漏长度及栅长,实现了高开关比和低漏电流的高性能器件,具有大记忆窗口和高可靠性。

Comments This work has been submitted to the IEEE for possible publication

详情
AI中文摘要

TiO2铁电场效应晶体管(FeFETs)与HfZrO2(HZO)铁电介电层和底部栅极拓扑结构相结合,用于神经形态系统的应用。通过改变铁电栅极堆叠厚度,制造了两种不同栅极拓扑结构的器件。通过改变源漏长度(LSD)和栅长(LG)研究了不同器件架构。器件具有高达10^7的高开/关比,低漏电流<10^-12 A。重复循环测试显示高可靠性和稳定的记忆窗口。器件具有从3到8 V的大记忆窗口。

英文摘要

TiO2 ferroelectric field effect transistors (FeFETs) with HfZrO2 (HZO) ferroelectric dielectric layers and bottom gate topology are fabricated for applications in neuromorphic systems. Two sets of devices are fabricated with different gate topologies by varying the thickness of the ferroelectric gate stack. Different device architectures are studied by varying the source drain length (LSD) and gate length (LG). The devices have high on/off ratios up to 10^7 with low leakage off currents <10^-12 A. Repeated cycle testing shows high reliability and a stable memory window. The devices have large memory windows ranging from 3 to 8 V.

2605.20403 2026-05-21 eess.AS

Causal Spatio-Temporal Sound Field Reconstruction

因果时空声音场重建

David Sundström, Filip Tronarp, Johan Lindström, Andreas Jakobsson

AI总结 本文提出了一种因果有限窗时空线性最小均方误差估计器,用于改进实时声音场重建,通过考虑频率成分间的相关性,提升了短窗重建性能。

详情
AI中文摘要

在声音场控制应用中,通常假设可以获取感兴趣区域的声音场准确表示。然而,从可用麦克风测量中重建声音场,尤其是在实时应用中,仅能获取因果测量,这是一个具有挑战性的问题。值得注意的是,因果时间窗口化观测引入了频率成分之间的相关性,使得独立处理每个频率带的声音场重建方法变得次优。本文提出了一种因果有限窗时空线性最小均方误差估计器,将声音场建模为由平稳时空随机源分布驱动的波动方程的解,从而诱导出具有物理解释的协方差函数。证明了该协方差函数与经典扩散场相干模型密切相关。由于计算复杂度随时空观测数量的增加而迅速增长,本文提出了一种预算受限的时空采样选择方法,以最小化后验重建方差。所提出的估计器和采样策略通过模拟和测量的声音场进行评估,展示了与频率域有限窗基线相比改进的短窗重建性能。

英文摘要

In sound field control applications, it is commonly assumed that one has access to an accurate representation of the sound field in the region of interest. This is a problematic assumption since the reconstruction of a sound field from available microphone measurements is especially challenging in real-time applications where only causal measurements are available. Notably, causal time-windowed observations introduce correlation between frequency components, making sound field reconstruction methods that process each frequency band independently sub-optimal. In this work, we formulate a causal finite-window spatio-temporal linear minimum mean-square error estimator for sound field reconstruction. The sound field is modeled as the solution to the wave equation driven by a stationary stochastic spatio-temporal source distribution, which induces a physically interpretable covariance function. It is shown that this covariance function is closely related to the classical diffuse-field coherence model. Since the computational complexity grows rapidly with the number of spatio-temporal observations, we formulate a budget-constrained spatio-temporal sample selection approach to minimize the posterior reconstruction variance. The proposed estimator and sampling strategy are evaluated using both simulated and measured sound fields, demonstrating improved short-window reconstruction compared to frequency domain finite-window baselines.

2605.20401 2026-05-21 cs.SE

A Semantic-Web Oriented Competency Model for Engineering Programs

面向语义网的工程课程能力模型

Nicolas Evain, Ernesto Exposito, Philippe Arnould

AI总结 本文提出了一种面向语义网的工程课程能力模型,通过将知识体系与能力框架相结合,设计出能够培养专业人才的课程体系,并提供可复制的方法和语义wiki基础设施来支持课程内容的协作维护。

Journal ref 48th International Conference on Software Engineering - IEEE SWEBOK Summit 2026 (ICSE 2026), IEEE/ACM, Apr 2026, Rio de Janeiro, Brazil

详情
AI中文摘要

尽管有全面的知识体系(BoKs)记录了软件工程、计算机科学、信息系统和新兴计算领域的核心知识,但将这些知识整合到连贯的能力导向课程中以培养专业人才的方法仍然不完善。本文提出了一种能力映射方法,通过连接知识体系和能力框架来设计计算课程。我们通过ISANUM,一个为期五年的工程学位项目,展示了该方法,该项目包含23项能力,分为五个主题块,每个块都明确映射到34个计算知识领域中定义的494个知识主题。该项目整合了三个专业路径(软件工程、数据工程与数据科学、信息技术)并包含必修的工作学习项目,确保毕业生在理论基础和实践工作能力方面得到发展。我们的贡献为计算教育者提供了一种可复制的方法,将知识体系转化为可评估的能力框架,并通过语义wiki基础设施(ISANUMpedia)支持课程内容的协作理解、维护和演变。

英文摘要

Despite comprehensive Bodies of Knowledge (BoKs) documenting core knowledge across software engineering, computer science, information systems, and emerging computing fields, a critical gap persists: methodologies for integrating this knowledge into coherent competency-based curricula that prepare graduates for professional careers remain underdeveloped. This paper presents a competency-mapping methodology that bridges Bodies of Knowledge and competency frameworks to design computing curricula. We demonstrate this methodology through ISANUM, a five-year engineering degree program featuring 23 competencies organized into five thematic blocks, each with explicit mappings to 494 knowledge topics from 34 Computing Knowledge areas defined in Computing Curricula 2020. The program integrates three specialized pathways (Software Engineering, Data Engineering \& Data Science, and Information Technology) with mandatory work-study programs, ensuring graduates develop both theoretical foundations and practical workplace competencies. Our contribution provides computing educators with a replicable methodology for translating Bodies of Knowledge into assessable competency frameworks, supported by a semantic wiki infrastructure (ISANUMpedia) enabling collaborative curriculum understanding, maintenance and evolution.

2605.20399 2026-05-21 stat.ME stat.AP

A duration-augmented binary Markov chain for rainfall occurrence with long dry spells

具有持续时间的二元马尔可夫链用于降雨发生与长干旱期

Antoine Doizé, Denis Allard, Philippe Naveau, Olivier Wintenberger

AI总结 本文提出了一种具有持续时间增强的二元马尔可夫链,用于模拟降雨发生与长干旱期,通过与交替再生成链建立联系,实现了对湿旱期持续时间分布的灵活参数建模,并在南欧200多个站点上应用,验证了该方法在刻画持久性和高分位数外推方面的有效性。

详情
AI中文摘要

模拟真实合理的湿期和旱期是天气生成器和气候影响研究中的核心任务。虽然有限阶马尔可夫链是标准方法,但它们由于内在的亚指数衰减特性,往往无法再现持久的干旱条件。我们通过引入持续时间增强的二元马尔可夫链来建模降雨发生。我们建立了与交替再生成链的联系,从而能够灵活地对湿期和旱期持续时间分布进行参数建模。我们使用两种从广义极值分布一般类中衍生出的适应性规范来建模这些分布,从而在各种气候条件下实现灵活的尾部行为。我们使用适应于每种规范的估计方法。我们的模型应用于南欧约200个站点,涵盖了多样的地中海和大陆性气候。我们将此框架与标准马尔可夫模型进行比较,以刻画持久性和高分位数外推。该方法具有通用性,可自然扩展到多状态设置或其他二元序列应用在环境统计中。

英文摘要

Simulating realistic wet and dry spells is central in weather generators and climate-impact studies. While finite-order Markov chains are standard, they often fail to reproduce persistent dry conditions due to their inherent subexponential decay. We model rainfall occurrence by introducing a duration-augmented binary Markov chain. We establish a link with alternating renewal chains, enabling flexible parametric modelling of wet and dry spell duration distribution. We model those using two regime-adapted specifications from the general class of extended Generalized Pareto Distributions, yielding flexible tail behaviour across various climates. We use estimation methods adapted to each specification. Our model is applied to around 200 stations in the South of Europe spanning diverse Mediterranean and continental climates. We compare this framework to standard Markov models in characterising persistence and high-quantile extrapolation. The approach is generic, extending naturally to multi-state settings or other binary sequence applications in environmental statistics.

2605.20398 2026-05-21 physics.atom-ph

Spatio-spectral vector light created by optical activity in rubidium vapor

由铷蒸气中的光学活性产生的空间-光谱矢量光

Richard Aguiar Maduro, Riaan P. Schmidt, Mustafa A. Al Khafaji, Craig J. A. Millar, Sphinx J. Svensson, Andrey Surzhykov, Adam Selyem, Sonja Franke-Arnold

AI总结 通过光学泵浦和矢量涡旋光束探测原子蒸气,研究光学活性在频率、偏振和空间自由度之间的关联,并实现高精度光谱学和磁强计的应用。

Comments 7 pages, 6 figures

详情
AI中文摘要

我们展示了一种泵浦-探测方案,其中原子蒸气被圆偏振光泵浦,并用矢量涡旋光束探测。泵浦在介质中诱导宏观磁化,导致频率依赖的圆双折射和双折射。涡旋探测器通过空间变化的偏振特性,将光学活性映射到透射光的空间结构上,从而在频率、偏振和空间自由度之间建立相关性。测量合适偏振成分的强度分布可实现空间分辨的偏振光谱学。我们展示了频率位移转化为图像旋转的现象,在共振时观察到每兆赫兹约98毫弧度的旋转。这些发现可能在高精度光谱学、磁强计和混合纠缠生成中找到应用。

英文摘要

We demonstrate a pump-probe scheme in which an atomic vapor is optically pumped with circularly polarized light and probed with a vector vortex beam. The pump induces a macroscopic magnetization in the medium, which gives rise to frequency-dependent circular dichroism and birefringence. The vortex probe, characterized by spatially varying polarization, maps this optical activity onto the spatial structure of the transmitted light, thereby generating correlations between the frequency, polarization, and spatial degrees of freedom. Measuring the intensity profile in a suitable polarization component then allows us to perform spatially resolved polarization spectroscopy. We demonstrate the translation of frequency shifts into an image rotation, observing on resonance a rotation in the order of 98 mrad per MHz. These findings may find applications in high-precision spectroscopy, magnetometry, and the generation of hybrid entanglement.

2605.20397 2026-05-21 math.GR math.LO math.OA

An $\ell^2$ Obstruction for Elementary Embeddings of Hyperbolic Groups

超几何群元素嵌入的 $\ell^2$ 障碍

Connor MacMahon

AI总结 本文研究了超几何群在第一阶逻辑下嵌入时 $\ell^2$ 零数的单调性,证明了非阿贝尔proper子群在无 torsion 超几何群中的元素嵌入下严格递增,并进一步展示了任意有限生成群的存在性嵌入的单调性。

Comments 8 pages, 2 figures

详情
AI中文摘要

一个群的第一 $\ell^2$ 零数在各种由第一阶逻辑产生的嵌入下是非递减的。利用 Perin 对此类包含的分类,证明了非阿贝尔proper子群在无 torsion 超几何群中的元素嵌入下严格递增。进一步证明了任意有限生成群的存在的嵌入的单调性。

英文摘要

The first $\ell^2$ Betti number of a group is non-decreasing under various embeddings arising from first order logic. Strict inequality is proved for elementary embeddings of non-abelian proper subgroups within torsion free hyperbolic groups using Perin's classification of such inclusions. The monotonicity is further demonstrated for existential embeddings of arbitrary finitely generated groups.

2605.20394 2026-05-21 eess.SP

Starlink Beacons for Passive LEO-Aided 9D Navigation

星链信标用于被动低轨卫星辅助的9D导航

Nisanur Camuzcu, Tiep M. Hoang, Alireza Vahid

AI总结 本文提出了一种端到端的低轨卫星辅助混合框架,通过融合GPS、星链下行信标和惯性测量单元(IMU)在9D(3D位置、3D速度和3D姿态)PNT系统中使用扩展卡尔曼滤波器(EKF)。研究通过提取星链下行信标调频率、基准信标调频率与OFDM衍生范围观测值,并将结果整合到惯性导航中,验证了星链调频率在GPS信号退化或间歇性不可用时对9D估计的补充作用。

Comments 5 pages, 8 figures, submitted to IEEE VTC 2026 Fall

详情
AI中文摘要

全球导航卫星系统(GNSS)是定位、导航和定时(PNT)的基础,但其低功率信号容易被阻挡或干扰,在对抗性环境中(如海上环境)存在PNT可用性缺口。本文提出了一种端到端的低轨卫星辅助混合框架,通过融合GPS、星链下行信标和惯性测量单元(IMU)在9D(3D位置、3D速度和3D姿态)PNT系统中使用扩展卡尔曼滤波器(EKF)。我们(i)通过将测量与卫星ID相关联提取星链下行信标调频率;(ii)在共同的处理/估计流程下将信标调频率与OFDM衍生范围观测值进行基准测试;(iii)将所得可观测量整合到惯性导航中。我们通过Fisher信息预测、蒙特卡洛模拟和硬件测量评估GPS/IMU、星链/IMU和GPS-星链-IMU系统。结果表明,星链调频率提供了有意义的补充PNT信息,并在GNSS退化或间歇性不可用时有助于9D估计。

英文摘要

Global Navigation Satellite Systems (GNSS) underpin positioning, navigation, and timing (PNT), yet their low-power signals are easily blocked or disrupted, leaving gaps in PNT availability in contested environments (e.g. maritime settings) where interference, spoofing, or denial can occur. A key practical need is an independent, ubiquitous aiding signal that can be tracked passively and fused with inertial sensing to sustain full navigation-state estimation without dedicated or cooperative infrastructure. This paper presents an end-to-end LEO-aided hybrid framework that fuses GPS, Starlink downlink beacons, and an inertial measurement unit (IMU) in a 9D (3D position, 3D velocity, and 3D attitude) PNT system using an extended Kalman filter (EKF). We (i) extract Doppler-rate from Starlink downlink beacon tones by associating measurements with satellite IDs, (ii) benchmark beacon Doppler-rate against OFDM-derived range observables under a common processing/estimation pipeline, and (iii) integrate the resulting observable into inertial navigation. We evaluate GPS/IMU, Starlink/IMU, and GPS-Starlink-IMU using Fisher-information predictions, Monte Carlo simulations, and hardware measurements. Results show that Starlink Doppler-rate provides meaningful complementary PNT information, and can aid 9D estimation when GNSS is degraded or intermittently unavailable.

2605.20387 2026-05-21 math.OC

An iterative Constraint Programming approach to integrate maximum workload constraints in preemptive jobshop scheduling

一种迭代约束编程方法用于在优先级作业车间调度中整合最大工作负载约束

Tanguy Terrien, Cyrille Briand

AI总结 本文提出了一种迭代约束编程方法,用于在优先级作业车间调度中有效整合最大工作负载约束,通过迭代引入工作负载约束和定制启发式方法,提高了求解效率。

Journal ref The 32nd International Conference on Principles and Practice of Constraint Programming, Jul 2026, Lisbon, Portugal

详情
AI中文摘要

在现实世界中优化调度往往需要考虑工作负载约束,特别是人力资源,以确保合规性、实施休息期或在工作时间范围内平衡工作负载。本文聚焦于在优先级作业车间调度中处理这一类约束,因为优先级在涉及人力资源时尤其相关(允许人员灵活切换任务)。优先级还为非优先级问题提供了理论见解,作为其放松。本文的主要贡献是一种约束编程方法,旨在在优先级设置中有效处理最大工作负载约束,而无需将活动分解为单位持续时间的任务(这可能在计算上是不可行的)。由于工作负载约束引入了显著的额外复杂性,我们进一步提出了一种方法,该方法迭代地将工作负载约束引入问题,并提出了专门设计以指导高效搜索的启发式方法。实验结果展示了我们的方法在大量实例上的有效性,突显了其与IBM的CP Optimizer等知名工业求解器的性能比较。

英文摘要

Optimizing schedules in real-world settings often requires considering workload constraints, specially for human resources, to ensure regulatory compliance, impose rest periods, or level the workload over the working horizon. This paper focuses on tackling this family of constraints in the context of preemptive jobshop scheduling, as preemption is particularly relevant when human resources are involved (allowing personnel to flexibly switch between tasks). Preemption also offers theoretical insights as a relaxation of non-preemptive problems. The main contribution of this paper is a Constraint Programming approach designed to handle effectively maximum workload constraints in a preemptive setting, without decomposing activities into unit-duration tasks (which may be computationally prohibitive). Since workload constraints introduce significant additional complexity, we further propose a method that iteratively introduces the workload constraints into the problem, along with tailored heuristics specifically designed to guide the search efficiently. The experimental results demonstrate the effectiveness of our approach on a large set of instances, highlighting its performance compared to a well-known industrial solver, IBM's CP Optimizer.

2605.20384 2026-05-21 cond-mat.mtrl-sci

Dataset-aware entropy-maximized active learning for machine-learned interatomic potentials

面向数据集的熵最大化主动学习用于机器学习的原子间势能函数

Meiyan Wang, Rishi Rao, Li Zhu

AI总结 本文提出了一种面向数据集的熵最大化主动学习框架,用于高效生成机器学习原子间势能函数(MLIPs)的训练数据。该方法结合了局部熵驱动的分子动力学与全局数据集感知过滤:每个配置的熵项使MD轨迹倾向于结构多样的快照,而全局熵度量,即整个数据集指纹协方差矩阵的对数行列式,仅选择那些提供真正新信息的配置。通过双协方差模式(每个原子用于无序结构,每个配置用于有序相)实现配置空间的广泛覆盖。结合预训练的基础模型(Allegro-OAM-L)和来自高斯重叠矩阵特征值的分析指纹梯度,该框架在训练集大小为10^2到10^3的熵选择DFT标记结构上,能够以近或亚毫电子伏/原子的精度生成高质量的领域特定势能函数。在三个涵盖不同键合类型和压力驱动相变的系统上进行了验证:碳(共价)、硅(共价/金属)和NaCl(离子)。在与随机分子动力学采样在匹配训练集大小(N=100到800)的对比学习曲线中,评估三个独立的训练集抽样,熵驱动采样在N=800时在三个系统上的分布保持测试中实现了约3到10倍的较低能量MAE,增益的大小取决于键合类型和随机-MD基线在训练集大小上的饱和程度。

Comments 29 pages, 5 figures

详情
AI中文摘要

我们提出了一种主动学习框架,用于高效生成机器学习原子间势能函数(MLIPs)的训练数据。该方法结合了局部熵驱动的分子动力学与全局数据集感知过滤:每个配置的熵项使MD轨迹倾向于结构多样的快照,而全局熵度量,即整个数据集指纹协方差矩阵的对数行列式,仅选择那些提供真正新信息的配置。我们采用双协方差模式(每个原子用于无序结构,每个配置用于有序相)以实现配置空间的广泛覆盖。结合预训练的基础模型(Allegro-OAM-L)和来自高斯重叠矩阵特征值的分析指纹梯度,该框架在训练集大小为10^2到10^3的熵选择DFT标记结构上,能够以近或亚毫电子伏/原子的精度生成高质量的领域特定势能函数。我们在三个涵盖不同键合类型和压力驱动相变的系统上进行了验证:碳(共价)、硅(共价/金属)和NaCl(离子)。在与随机分子动力学采样在匹配训练集大小(N=100到800)的对比学习曲线中,评估三个独立的训练集抽样,熵驱动采样在N=800时在三个系统上的分布保持测试中实现了约3到10倍的较低能量MAE,增益的大小取决于键合类型和随机-MD基线在训练集大小上的饱和程度。

英文摘要

We present an active learning framework for efficiently generating training data for machine-learned interatomic potentials (MLIPs). The method combines local entropy-driven molecular dynamics with global dataset-aware filtering: a per-configuration entropy term biases MD trajectories toward structurally diverse snapshots, while a global entropy measure, the log-determinant of the fingerprint covariance matrix of the entire dataset, selects only those configurations that provide genuinely new information. We employ dual covariance modes (per-atom for disordered structures and per-config for ordered phases) to achieve broad coverage of configuration space. Combined with a pre-trained foundation model (Allegro-OAM-L) and analytical fingerprint gradients from Gaussian overlap matrix eigenvalues, the framework produces high-quality domain-specific potentials with near- or sub-meV/atom accuracy on test data drawn from the same distribution at training-set sizes of order $10^{2}$ to $10^{3}$ entropy-selected DFT-labeled structures. We demonstrate the method on three systems spanning diverse bonding types and pressure-driven phase transitions: carbon (covalent), silicon (covalent/metallic), and NaCl (ionic). In learning curve comparisons against random molecular dynamics sampling at matched training set sizes ($N = 100$ to $800$), evaluated over three independent training-set draws per condition, entropy-driven sampling achieves a factor of approximately $3$ to $10$ lower energy MAE at $N = 800$ on in-distribution holdouts across the three systems, with the magnitude of the gain depending on the bonding type and the size at which the random-MD baseline saturates.