arXivDaily arXiv每日学术速递 周一至周五更新
2606.20460 2026-06-19 cond-mat.stat-mech 新提交

Scaling, fractal dynamics, and critical exponents in the equilibrium phase transition

平衡相变中的标度、分形动力学和临界指数

Adauto F. Souza, Henrique A Lima, Anderson L. R. Barbosa, Fernando A. Oliveira

AI总结 本文通过分数阶微分分析揭示了平衡相变中关联函数的标度行为、临界指数与分形几何之间的深层联系,为Ising、Potts、XY和Heisenberg模型提供了统一的几何解释。

Comments 6 pages, no figures

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AI中文摘要

统计方法对于理解具有多自由度的热力学系统至关重要。对于平衡系统,一个非常有用的方法是关联函数,它建立了依赖于空间位置x的场phi(x)与另一位置phi(x0)处的同一场之间的关联。Fisher [Journal of Mathematical Physics 5, 944322 (1964)] 引入了序参量涨落的自相关函数,这已成为理解平衡二级相变的重要数学工具。然而,他的分析局限于d维欧氏空间,并引入指数eta来修正T = Tc处关联函数的空间行为。在最近的工作中,Lima等人 [Phys. Rev. E 110, L062107 (2024)] 证明了现代分数阶微分分析对于完整描述Tc处的关联函数是必要的。在本研究中,我们强调了标度行为、临界指数和分形几何之间的深层联系。我们的结果为临界指数和分形维数提供了统一的几何解释,广泛适用于热力学相变。然而,该方法不适用于拓扑相变,因为拓扑相变缺乏局域序参量和相关的标度不变分形几何。我们验证了其对几个基石热力学模型的预测:Ising、Potts、XY和Heisenberg系统。

英文摘要

Statistical methods are essential for understanding thermodynamic systems with many degrees of freedom. For systems in equilibrium, a very useful method is that of correlation functions, which establish a correlation between a field phi(x), which depends on the spatial position x, and the same field evaluated at another position, phi(x0). Fisher [Journal of Mathematical Physics 5, 944322 (1964)] introduced the autocorrelation function for fluctuations of the order parameter, which has been an important mathematical tool for understanding second-order phase transitions in equilibrium. However, his analysis is restricted to a Euclidean space of dimension d, and an exponent eta is introduced to correct the spatial behavior of the correlation function at T = Tc. In a recent work, Lima et al. [Phys. Rev. E 110, L062107 (2024)] demonstrated that a modern fractional differential analysis is necessary for a complete description of the correlation function at Tc. In this study, we highlight the deep connection among scaling behavior, critical exponents, and fractal geometry. Our results provide a unified geometric interpretation of critical exponents and fractal dimensions, broadly applicable to thermodynamic phase transitions. However, the approach does not apply to topological phase transitions, which lack local order parameters and the associated scale-invariant fractal geometry. We verify its predictions for several cornerstone thermodynamic models: the Ising, Potts, XY, and Heisenberg systems.

2606.20445 2026-06-19 cond-mat.stat-mech hep-th quant-ph 新提交

Space-time duality approach to (inhomogeneous) integrable quenches

时空对偶方法在(非均匀)可积淬火中的应用

Riccardo Travaglino, Pasquale Calabrese, Katja Klobas, Bruno Bertini

AI总结 通过解决时空对偶方法的固有歧义,推导出一般量子淬火后纠缠增长和电荷涨落的闭式预测,并用精确解和数值模拟验证。

Comments 5 pages + appendices, 9 figures

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AI中文摘要

表征非平衡量子多体动力学的普适方面是本世纪物理学研究的关键目标之一。然而,由于缺乏研究远离平衡的相互作用量子物质的一般理论框架,进展受到阻碍。最近的一个突破是认识到几个关键的非平衡量,如纠缠增长率或有限子系统内守恒电荷的涨落,可以通过有效交换空间和时间角色的时空对偶与平衡性质相关联。这一观察使得能够借用平衡统计力学和热力学的工具和概念来研究非平衡现象。这一框架(称为时空对偶方法,SDA)的第一个原理证明由相互作用的可积系统提供,其中热力学性质通常可以精确表征,而动力学量通常超出解析范围。然而,随后的发展表明,SDA存在内在的歧义,限制了其对均匀淬火和由对称初始态产生的电荷涨落的适用性。在这里,我们从第一原理解决了这一歧义,并推导了一般量子淬火后纠缠增长和电荷涨落的闭式预测。我们将我们的结果与Rule 54量子元胞自动机的精确解析解以及XXZ链的大量TEBD模拟进行了基准测试。此外,我们表明,当专门针对纠缠熵时,我们的框架自然地再现了准粒子图像的预测。

英文摘要

Characterising the universal aspects of non-equilibrium quantum many-body dynamics is one of the key goals of this century's physics research. Progress, however, is hindered by the lack of general theoretical frameworks for studying interacting quantum matter far from equilibrium. A recent breakthrough has been the realization that several key non-equilibrium quantities, such as the rate of growth of entanglement or the fluctuations of conserved charges within finite subsystems, can be related to equilibrium properties through a space-time duality that effectively exchanges the roles of space and time. This observation effectively enables the study of non-equilibrium phenomena using tools and concepts borrowed from equilibrium statistical mechanics and thermodynamics. A first proof of principle of this framework, dubbed space-time duality approach (SDA), was provided by interacting integrable systems, where thermodynamic properties can often be characterized exactly, while dynamical quantities typically remain beyond analytical reach. Subsequent developments, however, revealed that the SDA suffered from an intrinsic ambiguity, restricting its applicability to homogeneous quenches and to charge fluctuations arising from symmetric initial states. Here we resolve this ambiguity from first principles and derive closed-form predictions for entanglement growth and charge fluctuations after general quantum quenches. We benchmark our results against the exact analytical solution of the Rule 54 quantum cellular automaton and extensive TEBD simulations of the XXZ chain. Moreover we show that, when specialised to the entanglement entropy, our framework naturally reproduces the predictions of the quasiparticle picture.

2606.20440 2026-06-19 cond-mat.quant-gas physics.atom-ph 新提交

Polaronic hybridization of atoms, dimers and trimers in a Bose-Einstein condensate

玻色-爱因斯坦凝聚中原子、二聚体和三聚体的极化子杂化

Carsten Robens, Arthur Christianen, Alexander Y. Chuang, Huan Q. Bui, Yiming Zhang, Richard Schmidt, Martin Zwierlein

AI总结 通过射频光谱实验,在钠玻色-爱因斯坦凝聚中观测到钾杂质与凝聚体形成的三体关联极化子杂化态,并用无自由参数的三能级模型解释主要光谱特征。

Comments 5+4 pages, 4+3 figures

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AI中文摘要

浸入玻色-爱因斯坦凝聚体(BEC)中的杂质形成的玻色极化子问题,已被预测具有由多个玻色子与杂质形成的束缚态所导致的强关联。尽管直接实验证据至今仍难以获得,但在这里我们观测到了玻色极化子中三体关联的清晰特征。我们对$^{23}$Na BEC中的$^{40}$K杂质进行射频光谱分析,识别出极化子杂化态,这些态可以理解为裸原子、NaK二聚体和Na$_2$K三聚体的叠加,通过相干粒子交换与凝聚体耦合。我们表明,主要光谱特征可由一个无自由参数的简单三能级模型描述。我们的工作展示了凝聚体环境如何相干地杂化不同组成和质量的束缚态,类似于粒子物理学中由Cabibbo-Kobayashi-Maskawa(CKM)矩阵描述的夸克味混合。

英文摘要

The Bose polaron problem of an impurity immersed in a Bose-Einstein condensate (BEC) has been predicted to feature strong correlations arising from bound states of multiple bosons with the impurity. While direct experimental evidence has so far remained elusive, here we observe clear signatures of three-body correlations in Bose polarons. We perform radiofrequency spectroscopy on $^{40}$K impurities in a BEC of $^{23}$Na and identify polaronic hybrid states that can be understood as superpositions of the bare atom, a NaK dimer and a Na$_2$K trimer, coupled through coherent particle exchange with the condensate. We show that the main spectroscopic features are captured by a simple three-level model without free parameters. Our work shows how a condensate environment can coherently hybridize bound states of different composition and mass, reminiscent of quark-flavor mixing described by the Cabibbo-Kobayashi-Maskawa (CKM) matrix in particle physics.

2606.20425 2026-06-19 cond-mat.str-el 新提交

Non-Hermitian Skin Effect Enhances Pairing Correlations in Moiré Hubbard Systems

非厄米趋肤效应增强莫尔哈伯德系统中的配对关联

Yang Zhou, Jianwen Chen, Ruipeng Wei

AI总结 本文发现非厄米趋肤效应通过通道选择性机制增强莫尔哈伯德系统中的配对关联,在非互易强度γ∈[0.5,1.2]t的“黄金窗口”内,边界态密度增大,局域配对倾向增强,双占据数非单调变化,配对磁化率在3×3团簇上提升98%。

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AI中文摘要

我们展示了非厄米趋肤效应(NHSE)可以通过通道选择性机制增强莫尔哈伯德系统中的配对关联:趋肤诱导的局域化放大了边界态密度,在非互易性γ∈[0.5,1.2]t的中间“黄金窗口”内增强了局域配对倾向。通过对具有开放边界的三角晶格上的非厄米哈伯德模型进行精确对角化,我们绘制了(U,γ)相图。双占据数D(γ)表现出非单调行为——先上升高达21%然后下降——反映了NHSE增强的边界配对与过度局域化之间的竞争。在3×3团簇上对配对磁化率χ_SC的分解揭示,NHSE具有通道选择性:它增强了局域配对(+21%),同时抑制了竞争的反铁磁关联(减少22%),因此总配对磁化率(由局域通道主导)在该团簇上增长了+98%。这些趋势通过独立的非厄米DMRG计算得到证实,并确立了有限团簇配对关联的增强,而非平凡的密度重新分布。我们不声称存在长程超导序。BCS标度估计将相同的配对响应信号转换为穹顶形的T_c(γ)特征,表明在相干驱动和储层主导的莫尔器件中具有实验可区分的响应。

英文摘要

We show that the non-Hermitian skin effect (NHSE) can enhance pairing correlations in moiré Hubbard systems through a channel-selective mechanism: skin-induced localization amplifies the boundary density of states, strengthening local pairing tendencies within an intermediate ``golden window'' of non-reciprocity $γ\in[0.5,1.2]\,t$. Using exact diagonalization of the non-Hermitian Hubbard model on triangular lattices with open boundaries, we map the $(U,γ)$ phase diagram. The double occupancy $D(γ)$ exhibits non-monotonic behavior -- rising by up to 21\% then declining -- reflecting a competition between NHSE-enhanced boundary pairing and over-localization. A decomposition of the pairing susceptibility $χ_{\mathrm{SC}}$ on the $3\times3$ cluster reveals that the NHSE acts \emph{channel-selectively}: it enhances on-site pairing ($+21\%$) while simultaneously suppressing competing antiferromagnetic correlations (22\% reduction), so that the total pairing susceptibility, dominated by the on-site channel, grows by $+98\%$ on that cluster. These trends are corroborated by an independent non-Hermitian DMRG calculation and establish an enhancement of finite-cluster pairing correlations rather than trivial density redistribution. We do not claim long-range superconducting order. A BCS scaling estimate converts the same pairing-response signal into a dome-shaped $T_c(γ)$ fingerprint, suggesting an experimentally distinguishable response in coherent-drive versus reservoir-dominated moiré devices.

2606.20403 2026-06-19 cond-mat.str-el cond-mat.stat-mech hep-th 新提交

Superconductivity and non-Fermi liquid metals in a charge-1/3 anyon fluid

电荷1/3任意子流体中的超导性和非费米液体金属

Zhengyan Darius Shi, T. Senthil

AI总结 本文通过掺杂ν=2/3 Jain分数量子霍尔绝缘体得到电荷1/3任意子流体,发现复合费米子描述下的味对称配对态导致SC*态(电荷-2e凝聚与Z2拓扑序共存),而低掺杂近似SU(3)对称区域实现非费米液体Z3正交金属。

Comments 7 pages, 1 figure, 1 table, 4 page appendices

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AI中文摘要

我们重新审视了通过掺杂$\nu = 2/3$ Jain分数量子霍尔绝缘体(FCI)得到的电荷1/3任意子流体。在标准的复合费米子描述中,掺杂的任意子分解为三种平移相关的次级复合费米子味,其规范介导的相互作用驱动了稳健的味间配对不稳定性。在我们之前的工作中,我们分析了一个味不对称的配对态,并得到了一个电荷有序的费米液体。受最近一篇论文的启发,我们考虑了一个替代的味对称配对态,并证明它是一个SC*态:一个电荷-$2e$凝聚体,与残余的$\mathbb{Z}_2$拓扑序共存。弱配对和强配对区域具有相同的本征拓扑序,但手征中心荷不同,分别为$c_- = 7/2$和$c_- = 2$。我们进一步展示了其他提出的有效场论如何适应相同的复合费米子描述,并论证了在掺杂驱动的FCI到超导体的转变中,局域任意子演化为Bogoliubov准粒子而非涡旋。在低掺杂下,我们识别出一个近似的SU(3)对称区域,其中系统实现了一个非费米液体$\mathbb{Z}_3$正交金属,具有三个电荷1/3费米口袋,没有尖锐的电子准粒子。最后,我们评论了各种可能基态的能量学,并讨论了对moire材料实验的启示。

英文摘要

We revisit the charge-1/3 anyon fluid obtained by doping the $ν= 2/3$ Jain fractional Chern insulator (FCI). In the standard composite fermion description, the doped anyons fractionalize into three translation-related flavors of secondary composite fermions, whose gauge-mediated interactions drive a robust inter-flavor pairing instability. In our previous work, we analyzed a flavor-asymmetric paired state and obtained a charge-ordered Fermi liquid. Inspired by a recent paper, we consider an alternative flavor-symmetric paired state and show that it is an SC* state: a charge-$2e$ condensate that coexists with residual $\mathbb{Z}_2$ topological order. The weak and strong pairing regimes share the same intrinsic topological order but differ in chiral central charge, giving $c_- = 7/2$ and $c_- = 2$. We further show how other proposed effective field theories fit within the same composite fermion description, and argue that across the doping driven FCI-to-superconductor transition, localized anyons evolve into Bogoliubov quasiparticles rather than vortices. At low doping, we identify an approximate SU(3)-symmetric regime in which the system instead realizes a non-Fermi liquid $\mathbb{Z}_3$ Orthogonal Metal with three charge-1/3 fermion pockets and no sharp electron quasiparticle. Finally, we comment on the energetics of various possible ground states and discuss implications for experiments in moire materials.

2606.20378 2026-06-19 cond-mat.mes-hall 新提交

Mixed Floquet Lattice model for gapless topology

无带隙拓扑的混合Floquet晶格模型

Goutham Vinjamuri, Ashutosh Dubey, Ankur Das

AI总结 研究在Floquet合成维度中实现时间反演破缺的Weyl半金属,发现混合Floquet晶格仅在动量分辨意义上捕获Weyl半金属拓扑,而实空间响应表现为Rice-Mele型泵浦结构。

Comments 6 pages with 2 figures and 1 supplement with 2 pages, 1 figure

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AI中文摘要

我们研究了在Floquet合成维度中实现时间反演破缺的Weyl半金属,该合成维度由两个不可公度驱动产生,遵循驱动合成晶格中拓扑频率转换的精神(PRX 7, 041008 (2017))。系统由混合$(1~\mathrm{实}+2~\mathrm{合成})$维设置中的一维晶格模型描述,其中驱动相位充当合成动量,并在混合Floquet能带结构中产生Weyl点。利用与这些能带简并相关的拓扑,我们分析了两个驱动之间的能量转移。我们发现,混合Floquet晶格仅在动量分辨意义上捕获Weyl半金属拓扑:对于固定的实动量$k_x$,功率转移测量$k_x$分辨的陈数并检测Weyl节点的分离。然而,完整的实空间响应在性质上不同。总功率转移不重现静态Weyl半金属相图,而是遵循有效的Rice-Mele型泵浦结构。因此,与完全带隙的拓扑绝缘体相反,无带隙的半金属相不能直接转化为Floquet合成维度。我们的结果揭示了驱动Weyl系统独特的动力学相结构,并建立了混合Floquet晶格作为探索非平衡无带隙拓扑的平台。

英文摘要

We investigate the realization of a time-reversal-broken Weyl semimetal in Floquet synthetic dimensions generated by two incommensurate drives, in the spirit of topological frequency conversion in driven synthetic lattices PRX 7, 041008 (2017). The system is described by a one-dimensional lattice model in a mixed $(1~\mathrm{real}+2~\mathrm{synthetic})$-dimensional setting, where the driving phases act as synthetic momenta and generate Weyl points in the mixed Floquet band structure. Using the topology associated with these band degeneracies, we analyze the energy transfer between the two drives. We find that the mixed Floquet lattice captures the Weyl-semimetal topology only in a momentum-resolved sense: for fixed real momentum $k_x$, the power transfer measures the $k_x$-resolved Chern number and detects the separation of the Weyl nodes. However, the full real-space response is qualitatively different. The total power transfer does not reproduce the static Weyl-semimetal phase diagram, but instead follows an effective Rice-Mele-type pumping structure. Thus, in contrast to fully gapped topological insulators, gapless semimetallic phases do not straightforwardly translate to Floquet synthetic dimensions. Our results reveal a distinct dynamical phase structure of driven Weyl systems and establish mixed Floquet lattices as a platform for exploring non-equilibrium gapless topology.

2606.20377 2026-06-19 cond-mat.mes-hall cond-mat.str-el 新提交

Charge imprinting biases topology of correlated insulator in hBN-aligned rhombohedral multilayer graphene

电荷印记偏向hBN对齐的菱方多层石墨烯中关联绝缘体的拓扑性质

Lei Qiao, Xin Lu, Fu-Chun Zhang, Jianpeng Liu

AI总结 通过Hartree-Fock计算,发现菱方多层石墨烯与hBN对齐时,关联绝缘体在特定层数和转角下最稳定,且hBN对齐通过电荷印记效应调控拓扑绝缘态的形成。

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AI中文摘要

与六方氮化硼对齐的菱方多层石墨烯(RMG-hBN)承载关联Chern相,但hBN堆叠的微观作用仍不清楚,特别是当活性载流子远离莫尔界面时。通过考虑层数、扭转角、位移场、填充和hBN对齐的Hartree-Fock计算,我们表明关联绝缘体在小扭转角和中等层数($N\simeq 6$)时最为稳健,此时带宽抑制与活性载流子波函数的层离域达到平衡。在填充$\nu=1$的莫尔远离条件下,绝缘态的拓扑性质受到电荷印记的强烈偏向:hBN对齐通过莫尔势塑造了界面附近占据的价带电荷纹理,该纹理通过长程库仑相互作用作为掺杂导带电子的远程静电模板。根据对齐方式,该模板倾向于支持与平庸绝缘体相关的三角电荷局域化,或与Chern绝缘体兼容的蜂窝状电荷网络。我们的结果确定了价带电荷纹理是远程莫尔界面控制多层石墨烯中关联拓扑的微观途径。

英文摘要

Rhombohedral multilayer graphene aligned with hexagonal boron nitride (RMG-hBN) hosts correlated Chern phases, but the microscopic role of hBN stacking remains unclear, especially when the active carriers are displaced away from the moiré interface. Using Hartree-Fock calculations over layer numbers, twist angles, displacement fields, fillings, and hBN alignments, we show that correlated insulators are most robust at small twist angles and intermediate layer number ($N\simeq 6$), where bandwidth suppression is balanced by layer delocalization of the wavefunctions of the active carriers. Under moiré-distant conditions at filling $ν=1$, the topology of the insulating state is strongly biased by charge imprinting: the hBN alignment shapes the occupied valence-band charge texture near the interface via moiré potential, which acts through long-range Coulomb interactions as a remote electrostatic template for doped conduction electrons. Depending on the alignment, this template favors either triangular charge localization associated with trivial insulators or honeycomb-like charge networks compatible with Chern insulators. Our results identify valence-band charge textures as a microscopic route by which a remote moiré interface controls correlated topology in multilayer graphene.

2606.20371 2026-06-19 cond-mat.mtrl-sci 新提交

Breaking symmetry to create a parallel-plate varactor dielectric with unparalleled microwave performance

打破对称性以创建具有无与伦比微波性能的平行板变容二极管介质

Florian Bergmann, Matthew R. Barone, Zishen Tian, Aiden Ross, Gerhard H. Olsen, Meagan C. Papac, Samuel Freed, Bryan T. Bosworth, Nicholas R. Jungwirth, Eric J. Marksz, Tomasz Karpisz, Noah Schnitzer, Lopa Bhatt, David A. Muller, Dylan Sotir, Akash Surampalli, Veronica Goian, Christelle Kadlec, Stanislav Kamba, Asher Hansen, Nathan Rongitsch, Dmitri A. Tenne, Ichiro Takeuchi, Long-Qing Chen, Lane W. Martin, Nathan D. Orloff, Darrell G. Schlom

AI总结 通过打破Ruddlesden-Popper相的晶体对称性,实现了低损耗、面外可调的平行板变容二极管介质薄膜,在10 GHz下优值提升十倍。

Comments 63 pages with 34 main manuscript pages and supplementary

Journal ref Nat Electron (2026)

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AI中文摘要

电压可调电容器(变容二极管)是微波电路的关键。可调介质变容二极管在几乎所有相关指标上优于竞争技术,但通常存在高介电损耗。相比之下,Ruddlesden-Popper(RP)介质薄膜具有极低的微波损耗。然而,直到最近,它们的晶体对称性决定了面内器件结构,阻碍了有利于最小化尺寸和最大化可调介质中电场的面外平行板变容二极管设计。在理论指导下,我们报道了类似于广泛研究的可调微波介质BaxSr1-xTiO3的RP相。将这些相同的原子组装成第一个具有打破面外对称性的RP相,我们实现了低损耗、面外可调的介质薄膜。性能最高的薄膜,即A = Ba0.45Sr0.55且n = 8的(ATiO3)nAO薄膜,在10 GHz下将面外可调介质的优值提升了十倍,为新一代可调单片微波集成电路铺平了道路。

英文摘要

Voltage-tunable capacitors (varactors) are key to microwave circuits. Tunable dielectric varactors outperform competing technologies in almost every relevant metric but usually suffer from high dielectric loss. In contrast, Ruddlesden-Popper (RPs) dielectric thin films have remarkably low microwave loss. Unfortunately, their crystallographic symmetry has until recently dictated an in-plane device structure, precluding the favorable out-of-plane parallel-plate varactor design for minimized size and maximized electric field in the tunable dielectric. Guided by theory, we report RPs akin to the widely studied tunable microwave dielectric BaxSr1-xTiO3. Assembling these same atoms into the first RP phase with broken out-of-plane symmetry, we achieve a low-loss, out-of-plane tunable dielectric thin film. The highest performing film, (ATiO3)nAO film with A = Ba0.45Sr0.55 and n = 8, unlocks a tenfold improvement in the figure of merit for out-of-plane tunable dielectrics at 10 GHz, paving the way for a new generation of tunable monolithic microwave integrated circuits.

2606.20349 2026-06-19 cond-mat.mtrl-sci 新提交

Effective masses, Burstein-Moss shift, and bandgap renormalization in degenerate Al-doped ZnO from broadband ellipsometry and Hall measurements

简并Al掺杂ZnO中的有效质量、Burstein-Moss位移和带隙重整化:来自宽带椭偏和霍尔测量的研究

S. Mishra, L. A. Enrique, D. Cespedes, E. Perez, E. Serquen, F. Bravo, P. Llontop, F. Ruske, L. Korte, J. A. Guerra

AI总结 通过全局拟合载流子浓度依赖的带隙和等离子体能量,结合宽带椭偏和霍尔测量,提取简并半导体的电子和空穴有效质量,并分离Burstein-Moss位移和带隙重整化。

Comments Supplementary material supporting this manuscript will be available upon reasonable request from contact authors

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AI中文摘要

开发了一种综合方法,通过同时全局拟合带隙和等离子体能量对载流子浓度的依赖性,并明确考虑能带非抛物性,来提取简并半导体中的电子和空穴有效质量。宽带光谱椭偏与霍尔效应分析相结合,能够准确确定带隙、等离子体能量和载流子浓度。利用基于Elliott的模型(包含重叠激子跃迁和Urbach尾)对溅射Al掺杂ZnO薄膜在基本吸收区的介电函数进行建模,而自由载流子吸收则通过修正的Sernelius公式描述。通过控制沉积和后退火实现了宽范围的载流子浓度,揭示了电子有效质量的变化和与抛物型色散的偏离。比较了两种非抛物模型:Pisarkiewicz模型(假设球对称带,采用费米-狄拉克分布的阶跃函数近似)和Nilsson模型(包含热效应和杂质效应)。后者能够准确捕捉能带非抛物性,得到的有效质量和非抛物性参数与带隙演化一致。该方法定量分离了Burstein-Moss位移和带隙重整化,在宽浓度范围内重现了载流子依赖的带隙位移。忽略价带贡献会引入系统偏差。进一步利用等离子体极化和随机相位近似评估带隙重整化,强调了多体屏蔽的重要性。该框架还能够确定Mott临界浓度和基本吸收边起始点。综合来看,这些结果为提取能带结构参数和带隙位移建立了一种可靠的方法,并可推广到其他透明导电氧化物。

英文摘要

A comprehensive methodology is developed to extract electron and hole effective masses in degenerate semiconductors through a simultaneous global fit of carrier concentration dependence of bandgap and plasma energy, explicitly incorporating band nonparabolicity. Broadband spectroscopic ellipsometry combined with Hall effect analyses enables accurate determination of the bandgap, plasma energy and carrier concentrations. The dielectric function of sputtered Al-doped ZnO thin films are modeled in the fundamental absorption region using an Elliott based model with overlapping excitonic transitions and Urbach tails, while free carrier absorption is described by a modified sernelius formula. Wide carrier concentrations are achieved via controlled deposition and post-annealing, revealing changes in electron effective masses and deviations from parabolic dispersion. Two nonparabolic models are compared, Pisarkiewicz, assuming spherically symmetric band with a step-function approximation of the Fermi-Dirac distribution and Nilsson, incorporating thermal and impurity effects. The latter is shown to capture accurately band nonparabolicity, yielding effective masses and nonparabolicity parameter consistent with bandgap evolution. This approach quantitatively separates Burstein-Moss shift and bandgap renormalization, reproducing carrier dependent bandgap shifts across a wide concentration range. Neglecting valence band contributions introduces systematic bias. Bandgap renormalization is further evaluated using plasmon pole and random phase approximations, underscoring the importance of many-body screening. This framework also enables determination of the Mott critical concentration and the fundamental absorption edge onset. Collectively, these results establish a reliable methodology for extracting band-structure parameters and bandgap shifts, extendable to other transparent conducting oxides.

2606.20339 2026-06-19 cond-mat.mes-hall 新提交

Diagnosing the origin of quantum oscillation beating in graphene

诊断石墨烯中量子振荡拍频的起源

Akash Adhikary, Sunit Das, Divya Sahani, Aveek Bid, Amit Agarwal

AI总结 通过分析拍频节点对载流子密度和磁场的依赖关系,区分了应变诱导赝磁场、谷不平衡、自旋轨道耦合等机制,并推导出不同机制下的标度关系。

Comments 15 pages, 4 figures. Suggestions and feedback are highly appreciated

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AI中文摘要

磁量子振荡通常在反比磁场中呈现周期性,当两个相近频率干涉时,其振幅会出现拍频。在基于石墨烯的六方系统中,这种拍频可能源于应变诱导的赝磁场、不等谷布居、谷依赖能移、自旋轨道耦合引起的能带分裂或Kekulé畸变。这里,我们展示拍频节点的载流子密度和磁场依赖性可以区分这些机制。从Onsager量子化关系出发,我们推导了拍频节点的临界载流子密度$N_c$作为临界磁场$B_c$函数的标度关系。赝磁场给出$N_c\propto B_c^2$,而与密度无关的谷不平衡给出$N_c\propto B_c$。由类塞曼自旋轨道耦合引起的常数狄拉克带能量分裂也给出二次场标度,但具有不同的节点序列:对于赝磁场,$N_{c,j}\propto(2j+1)B_{c,j}^2$;对于能量分裂,$N_{c,j}\propto(2j+1)^2B_{c,j}^2$,其中$j$标记拍频节点指数。这些结果为石墨烯基系统中谷依赖和自旋依赖能带分裂的不同微观起源提供了定量约束。

英文摘要

Magnetic quantum oscillations are usually periodic in inverse magnetic field, and their amplitude can show beating when two nearby frequencies interfere. In graphene-based hexagonal systems, such beating can arise from strain-induced pseudomagnetic fields, unequal valley populations, valley-dependent energy shifts, spin-orbit coupling-induced band splitting, or Kekulé distortions. Here, we show that the carrier density and magnetic field dependence of the beating nodes can distinguish these mechanisms. Starting from Onsager's quantization relation, we derive scaling relations for the critical carrier density $N_c$ for the beating nodes as a function of critical magnetic field $B_c$. A pseudomagnetic field gives $N_c\propto B_c^2$, whereas a density-independent valley imbalance gives $N_c\propto B_c$. A constant Dirac-band energy splitting by Zeeman-like spin-orbit coupling also gives quadratic field scaling, but with a different node sequence: $N_{c,j}\propto(2j+1)B_{c,j}^2$ for a pseudomagnetic field and $N_{c,j}\propto(2j+1)^2B_{c,j}^2$ for energy splitting, where $j$ labels the beating node indices. These results provide quantitative constraints on different microscopic origins of valley- and spin-dependent band splittings in graphene-based systems.

2606.20321 2026-06-19 cond-mat.mtrl-sci 新提交

Tunable Flat Bands and magnetism in Triangulene-based Superatomic Graphene

基于三角烯的超原子石墨烯中的可调平带与磁性

Wenya Zhai, Tingfeng Zhang, Fengkun Chen, Xiuqin Lu, Yunlong Xia, Zengfu Ou, Ye Chen, Donghui Guo, Meifang Zhu, Zhengfei Wang, Jingcheng Li

AI总结 通过磷掺杂三角烯自下而上合成超原子石墨烯,利用STM/S证实其狄拉克带和平带电子结构,DFT揭示平带源于面内p_x,y轨道并导致半金属性,氧功能化实现电子结构与磁序的可调调控。

Comments arXiv admin note: substantial text overlap with arXiv:2411.01108

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AI中文摘要

超原子石墨烯平台承载着丰富的平带驱动的奇异量子性质,但其实验实现仍具挑战。本文报道了以磷掺杂三角烯为构筑单元,通过自下而上的表面合成方法制备超原子石墨烯。扫描隧道显微镜和光谱测量解析了所制备超原子石墨烯的明确蜂窝晶格,并展示了其特征性的狄拉克带和平带电子结构。密度泛函理论计算表明,平带源于磷掺杂三角烯单元的面内p_x,y型前沿轨道,导致本征半金属行为。此外,分子前驱体的氧功能化实现了电子结构和磁序的确定性调控。该工作为设计具有可调平带性质的相关量子材料建立了通用平台。

英文摘要

Superatomic graphene platforms host a rich portfolio of flat-band-driven exotic quantum properties, yet their experimental realization remains challenging. Here, we report the bottom-up on-surface synthesis of superatomic graphene using phosphorus-doped triangulene as building blocks. Scanning tunneling microscopy and spectroscopy measurements resolve the well-defined honeycomb lattice of as-fabricated superatomic graphene and demonstrate the characteristic Dirac band and flat band electronic structures. Density functional theory calculations reveal that the flat bands originate from the in-plane p$_x,_y$-like frontier orbitals of the phosphorus-doped triangulene units, leading to intrinsic half-metallic behavior. Furthermore, oxygen functionalization of the molecular precursor enables deterministic modulation of the electronic structure and magnetic ordering. This work establishes a general platform for designing correlated quantum materials with tunable flat band properties.

2606.20317 2026-06-19 cond-mat.supr-con 新提交

Thermal reconstruction as a method of substrate preparation for highly crystalline superconducting TiN resonators

热重构作为高结晶超导TiN谐振器衬底制备的方法

Thomas J. Smart, Marc Neis, Janine Lorenz, Marcello P. Guardascione, Roudy Hanna, Michael Schleenvoigt, Yuan Gao, Joscha Domnick, Benjamin Bennemann, Abdur Rehman Jalil, Jin Hee Bae, Harsh Bhardwaj, F. Stefan Tautz, Felix Lüpke, Detlev Grützmacher, Rami Barends, Pavel A. Bushev, Peter Schüffelgen

AI总结 本文提出用CO₂激光热退火使蓝宝石衬底重构为(√31×√31)R±9°结构,替代化学清洗用于外延生长,制备的TiN薄膜结晶性更好,谐振器单光子内禀品质因数超10⁶。

Comments 12 pages, 9 figures

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AI中文摘要

在蓝宝石上实现高质量晶体薄膜生长需要充分的衬底制备,通常通过使用强化学清洗来实现。通过CO$_2$激光束直接热重构蓝宝石衬底,可能提供一种无需任何化学处理的替代外延衬底制备方法。在本工作中,我们证明了将蓝宝石热退火至其($\sqrt{31}$$\times$$\sqrt{31}$)$R$$\pm$9°重构是蓝宝石衬底的一种有效替代制备技术。在这些衬底上通过等离子体辅助分子束外延生长的TiN薄膜,其结晶性优于在化学清洗的蓝宝石衬底上生长的薄膜。由这些薄膜制备的超导谐振器表现出相似的性能,对于两种衬底制备方法,许多谐振器在单光子水平的内禀品质因数均大于10$^6$。

英文摘要

High quality crystalline growth of a thin film on sapphire requires sufficient substrate preparation, often achieved via the use of aggressive chemical cleaning. Direct thermal reconstruction of the sapphire substrate via a CO$_2$ laser beam may allow for an alternative way to prepare the substrate for epitaxy without the use of any chemical processing. Within this work, we demonstrate that thermal annealing of sapphire into its ($\sqrt{31}$$\times$$\sqrt{31}$)$R$$\pm$9° reconstruction is a valid alternative preparation technique for sapphire substrates. TiN films grown via plasma-assisted molecular beam epitaxy upon these substrates exhibit greater crystallinity than those grown on chemically cleaned sapphire substrates. Superconducting resonators fabricated from these films exhibit similar performance, with many possessing internal quality factors at single photon levels greater than 10$^6$ for both substrate preparation methods.

2606.20309 2026-06-19 cond-mat.str-el cond-mat.supr-con 新提交

Fractional excitations in Kitaev quasi-one-dimensional chain

Kitaev准一维链中的分数激发

Ritwika Majumder

AI总结 基于截断蜂窝几何构造准一维Kitaev自旋链,通过马约拉纳能带结构、拓扑相变及边缘态研究分数激发,并分析动态自旋关联函数中的连续谱特征。

Comments 9 pages, 6 figures

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AI中文摘要

Kitaev蜂窝模型因其量子自旋液体基态、分数化马约拉纳激发和拓扑性质而备受关注。受这些特征启发,我们引入一种从截断蜂窝几何导出的准一维Kitaev-like自旋链。所得马约拉纳能带结构包含色散带和平带,并在临界各向异性处能隙闭合,区分平凡拓扑相和手性拓扑相。在开边界条件下,拓扑区域存在受手性对称性保护的零能边缘模,使系统属于具有量子化绕数的BDI对称类。在激发谱中,局域化plaquette模出现在零能附近,并可通过引入负plaquette畴进行调控。动态自旋关联函数揭示了与分数激发相关的宽连续谱,以及来自边缘马约拉纳模的特征低能谱权重。这些特征将本系统与传统海森堡自旋链区分开来,并为手性拓扑序提供了实验可观测的指纹。因此,我们的模型在二维Kitaev自旋液体和Kitaev一维量子线之间建立了概念桥梁。

英文摘要

The Kitaev honeycomb model has attracted significant interest due to its quantum spin liquid ground state, fractionalized Majorana excitations, and topological properties. Motivated by these features, we introduce a quasi-one-dimensional Kitaev-like spin chain derived from a truncated honeycomb geometry. The resulting Majorana band structure contains both dispersive and flat bands, with a gap closing at a critical anisotropy that separates trivial and chiral topological phases. Under open boundary conditions, the topological regime hosts zero-energy edge modes protected by chiral symmetry, placing the system in the BDI symmetry class with a quantized winding number. In the excited spectrum, localized plaquette modes emerge near zero energy and can be tuned by introducing domains of negative plaquettes. The dynamical spin correlation function reveals broad continua associated with fractionalized excitations, together with characteristic low-energy spectral weight from edge Majorana modes. These features distinguish the present system from conventional Heisenberg spin chains and provide experimentally relevant fingerprints of chiral topological order. Our model thus establishes a conceptual bridge between the two-dimensional Kitaev spin liquid and Kitaev's one-dimensional quantum wire.

2606.20296 2026-06-19 cond-mat.str-el 新提交

All-In-All-Out Pyrochlore Iridates as Noncollinear Spin-Orbit Coupled Counterparts of Altermagnets

全进全出烧绿石铱酸盐作为交变磁体的非共线自旋-轨道耦合对应物

Yang Yang, Turan Birol, Rafael M. Fernandes, Natalia B. Perkins

AI总结 通过微观模型证明,烧绿石铱酸盐中的全进全出态构成强自旋-轨道耦合稳定的d波交变磁体的非共线对应物,并揭示其对称性导致的能带分裂特征。

Comments 23 pages, 4 figures

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AI中文摘要

交变磁体是在没有净磁化和自旋-轨道耦合(SOC)的情况下表现出动量依赖自旋分裂的共线磁有序态。然而,相关的自旋分裂模式也可能出现在具有大SOC的非共线磁系统中。这里,我们通过微观模型证明,烧绿石铱酸盐中的全进全出(AIAO)态构成了由强SOC稳定的$d$波交变磁体的非共线对应物。从烧绿石晶格上的微观$j_{\mathrm{eff}} = 1/2$紧束缚模型出发,我们证明了电子相互作用有利于AIAO相,并分析了其对称性。我们表明,AIAO序参量变换为$A_{2g}^{-}$八极磁矩,打破时间反演对称性,同时保持反演和零净磁化。通过群论分析和平均场计算,我们证明这种对称性强制了自旋极化的动量依赖的能带简并提升,类似于共线$d$波立方交变磁体,但也导致了零动量处的能带分裂。我们表明,后一特征由类似于立方半导体的Luttinger-Kohn模型的低能模型描述。我们的结果将烧绿石铱酸盐确定为交变磁性的非共线对应物的平台,并为自旋-轨道耦合材料中的自旋分裂现象提供了通用的对称性框架。

英文摘要

Altermagnets are collinear magnetically ordered states that exhibit momentum-dependent spin splitting in the absence of net magnetization and spin-orbit coupling (SOC). Related spin-splitting patterns, however, can also emerge in noncollinear magnetic systems with large SOC. Here we show, via a microscopic model, that the all-in-all-out (AIAO) state in pyrochlore iridates constitutes a noncollinear counterpart of a $d$-wave altermagnet stabilized by strong SOC. Starting from a microscopic $j_{\mathrm{eff}} = 1/2$ tight-binding model on the pyrochlore lattice, we demonstrate that electronic interactions favor the AIAO phase and analyze its symmetry properties. We show that the AIAO order parameter transforms as an $A_{2g}^{-}$ octupolar magnetic moment, breaking time-reversal symmetry while preserving inversion and zero net magnetization. Using group-theory analysis and mean-field calculations, we demonstrate that this symmetry enforces both a spin-polarized momentum-dependent lifting of band degeneracies that is similar to that of a collinear $d$-wave cubic altermagnet, but also a band splitting at zero-momentum. We show that the latter feature is captured by a low-energy model similar to the Luttinger-Kohn model for cubic semiconductors. Our results identify pyrochlore iridates as a platform for noncollinear counterparts of altermagnetism and provide a general symmetry framework for spin-split phenomena in spin-orbit coupled materials.

2606.20294 2026-06-19 cond-mat.soft cond-mat.mes-hall cond-mat.stat-mech 新提交

Multi-particle gates on driven one-dimensional paths: probing deep traps

驱动一维路径上的多粒子门:探测深陷阱

Harsh Jain, Shankar Ghosh, Archishman Raju

AI总结 研究驱动过阻尼胶体粒子在具有深势阱的周期性路径上的单列输运,发现当粒子数超过临界值时,粒子流从零变为有限,并呈现集体相关运动,通过数值模拟和光学涡旋实验验证。

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AI中文摘要

我们研究了驱动过阻尼胶体粒子在具有深势阱的周期性路径上的单列输运。在小陷阱极限(即陷阱尺寸小于粒子尺寸)下,当路径上的粒子数超过临界数$n_c$时,粒子流从零转变为有限。超过此阈值,$n_c$个粒子在陷阱后聚集,表现出集体相关运动。剩余的“额外”粒子循环流动,产生有限电流。我们通过过阻尼布朗动力学模拟数值研究了这一现象,并展示了在光学涡旋中驱动的微米级胶体粒子的实验实现。利用我们的实验观测,我们给出了表征深达数百$k_BT$的势阱的结果。

英文摘要

We study single-file transport of driven overdamped colloidal particles on a periodic path with deep potential wells. In the small trap limit (i.e., trap size smaller than particle size), the particle current transitions from zero to finite as the number of particles on the path exceeds a critical number $n_c$. Beyond this threshold, $n_c$ particles cluster behind the trap, demonstrating collective correlated motion. The remaining `extra' particles circulate, giving a finite current. We study this phenomenon numerically using overdamped Brownian dynamics simulations, and present an experimental realization of this behaviour for micron-scale colloidal particles driven in an optical vortex. Using our experimental observations, we present results characterizing potential wells as deep as several hundred $k_BT$.

2606.20281 2026-06-19 cond-mat.quant-gas quant-ph 新提交

Arrival times of an atomic Bose-Einstein condensate

原子玻色-爱因斯坦凝聚体的到达时间

Pascal Naidon, Lucas Happ, Denis Boiron

AI总结 研究在探测器靠近陷阱的未探索区域中,原子玻色-爱因斯坦凝聚体的飞行时间分布,通过解析和数值求解含时Gross-Pitaevskii方程,分析相互作用对到达时间分布的影响。

Comments 13 pages, 11 figures

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AI中文摘要

在实验未探索的区域中,即探测器靠近凝聚体陷阱的情况下,理论上研究了原子玻色-爱因斯坦凝聚体的飞行时间。在该区域,如何计算到达探测器的到达时间分布尚无共识。对于非相互作用粒子,过去已有不同的理论预测。本文分析了这些预测如何因相互作用的玻色-爱因斯坦凝聚体而改变。为此,解析和数值求解了含时Gross-Pitaevskii方程。

英文摘要

The times of flight of an atomic Bose-Einstein condensate are theoretically investigated in the experimentally unexplored regime corresponding to detection close to the trap of the condensate. In this regime, there is no consensus on how to calculate the distribution of times of arrival onto the detector. For non-interacting particles, distinct theoretical predictions have been made in the past. This work analyses how these predictions are modified for an interacting Bose-Einstein condensate. For this purpose, a time-dependent Gross-Pitaevskii equation is solved analytically and numerically.

2606.20279 2026-06-19 cond-mat.supr-con 新提交

Spin transport in a normal meta-altermagnetic superconducting nanowire junction

正常金属-交变磁超导纳米线结中的自旋输运

Xing-Jian Yi, Yi-Xin Dai, Yue Mao, Qing-Feng Sun

AI总结 提出在交变磁超导纳米线中实现自旋三重态超导和自旋超流,通过非平衡格林函数方法证明正常金属-交变磁超导纳米线界面存在非零等自旋安德烈夫反射,并系统研究自旋偏压下的自旋输运特性。

Journal ref Phys. Rev. B 113, 134502 (2026)

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AI中文摘要

自旋三重态超导体被认为是实现无耗散自旋输运的有前景平台,其中自旋电流由自旋三重态库珀对携带。在本文中,我们提出可以在交变磁超导纳米线中工程化自旋三重态超导和自旋超流,其中一维纳米线放置在s波超导体表面并与交变磁体邻近。利用非平衡格林函数方法,我们证明了在正常金属-交变磁超导纳米线界面存在非零等自旋安德烈夫反射系数,从而验证了自旋三重态库珀对的注入。此外,我们系统研究了该混合系统在自旋偏压下的自旋输运特性。我们的结果表明,这些特性可以通过化学势和自旋偏压方向有效调控。我们的提议为实现无耗散自旋输运提供了一条途径。

英文摘要

Spin triplet superconductors are considered a promising platform for dissipationless spin transport, where spin currents are carried by spin triplet Cooper pairs. In this paper, we propose that the spin triplet superconductivity and spin supercurrent can be engineered in an altermagnetic superconducting nanowire, where a one-dimensional nanowire is placed on the surface of an s-wave superconductor and in proximity to the altermagnet. Using the nonequilibrium Green's function method, we demonstrate a nonzero equal spin Andreev reflection coefficient at the normal metal-altermagnetic superconducting nanowire interface, thereby verifying the injection of spin triplet Cooper pairs. Furthermore, we systematically investigate the spin transport properties in this hybrid system under a spin bias. Our results demonstrate that these properties can be effectively tuned by the chemical potential and spin bias orientation. Our proposal provides a pathway toward realizing dissipationless spin transport.

2606.20275 2026-06-19 cond-mat.mtrl-sci 新提交

Exciton Transport in Disordered Perovskite Nanocrystal Solids

无序钙钛矿纳米晶固体中的激子传输

Simon Solari, Enrique Arévalo Rodríguez, Antonella Cutrupi, Amalia Coro, Marc Meléndez, Alicia De Andrés, Almudena Torres-Pardo, Beatriz H. Juárez, Ferry Prins

AI总结 研究揭示在铅卤钙钛矿纳米晶固体中,能量无序而非结构无序主导激子传输效率,长烷基链配体虽提高单分散性却因增强量子限域效应导致传输效率降低。

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AI中文摘要

溶液处理的胶体铅卤钙钛矿(LHP)纳米晶(NC)薄膜在光电器件如发光二极管(LED)、激光器和太阳能电池中显示出巨大潜力。然而,这些混合LHP NC固体表现出不可忽略的尺寸和形状多分散性,这引入了结构和能量无序。在这里,我们解析了激子在空间、时间和能量上的动力学,以阐明不同形式无序(结构和能量)对激子传输的影响。我们发现,无序敏感地依赖于合成中使用的烷基胺配体的长度。较短的烷基链长度导致高多分散性,而较长的烷基链导致更单分散和更小的颗粒,其中量子限域变得更加显著,从而增加能量无序。引人注目的是,我们发现具有长烷基链配体的NC固体中激子传输效率较低,尽管其具有显著更单分散的集合。这表明能量无序而非结构无序是预测这些材料中激子传输的主导因素。这些发现揭示了配体工程在设计基于混合LHP NC的高性能光电器件中的关键作用,为无序系统中的能量传输动力学提供了新见解,并突显了这些材料在先进光子学和光电子学应用中的多功能性。

英文摘要

Solution-processed thin films of colloidal lead halide perovskite (LHP) nanocrystals (NCs) show great potential for the implementation into optoelectronic devices such as light-emitting diodes (LEDs), lasers, and solar cells. However, these hybrid LHP NC solids exhibit non-negligible size and shape polydispersity, which introduces both structural and energetic disorder. Here, we resolve the exciton dynamics in space, time, and energy to elucidate the impact of different forms of disorder (structural and energetic) on exciton transport. We show that the disorder depends sensitively on the length of the alkylamine ligand used in the synthesis. While shorter alkyl chain lengths lead to high polydispersity, longer alkyl chains lead to more monodispersed and smaller particles where quantum confinement becomes more pronounced and, consequently, lead to increased energetic disorder. Strikingly, we find that exciton transport is less efficient in NC solids with long alkyl chain ligands, despite having a significantly more monodisperse ensemble. This demonstrates that energetic disorder, rather than structural disorder, is the dominant factor for predicting exciton transport within these materials. These findings reveal the critical role of ligand engineering in designing high-performance optoelectronic devices based on hybrid LHP NCs, providing new insights into energy transport dynamics in disordered systems and highlighting the versatility of these materials for advanced photonic and optoelectronic applications.

2606.20262 2026-06-19 cond-mat.mtrl-sci cond-mat.mes-hall physics.optics quant-ph 新提交

Anomalous magneto-optical response at $\mathrm{RuO_2 / WSe_2}$ van der Waals interface

RuO₂/WSe₂范德华界面处的异常磁光响应

Muhammad Hassan Shaikh, Abhijith Puthiya Veettil, Collin Maurtua, Dai Q. Ho, Subhash Bhatt, David T. Plouff, Malitha Gulawita, Kenji Watanabe, Takashi Taniguchi, John Q. Xiao, Anderson Janotti, Chitraleema Chakraborty

AI总结 通过磁近邻效应在RuO₂/WSe₂异质结中探测到RuO₂表面弱磁性,发现低于55K时激子能量异常偏移和谷分裂反常,表明界面交换场主导谷态,为研究争议性磁性材料提供了光学探针。

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AI中文摘要

二氧化钌(RuO₂)被提出作为交替磁性候选材料,尽管其磁基态仍存在争议。本文利用由单层二硒化钨(WSe₂)置于(001)取向RuO₂薄膜表面构成的范德华异质结中的磁近邻效应(MPE),探测RuO₂表面的弱界面磁态。温度依赖的磁光光谱揭示,在55 K以下出现异常的激子能量偏移和偏离常规Varshni行为,而这些现象在封装的WSe₂对照样品中不存在。该异常偏移在相反磁场极性的场冷却下符号反转,表明其磁起源。偏振分辨测量进一步显示,WSe₂/RuO₂中的谷分裂几乎与场无关且波动,与对照裸WSe₂样品中观察到的常规线性塞曼分裂形成强烈对比。这些结果表明,谷态主要由与RuO₂中弱表面磁态相关的界面交换场主导,而在所施加的磁场范围内不产生常规线性塞曼响应。重要的是,该方法无需引入额外铁磁层即可直接光学探测涌现的表面磁性,将基于MPE的光学探测定位为研究弱表面磁性的工具,并为研究具有争议性磁态的磁性材料提供了新可能性。

英文摘要

Ruthenium dioxide ($\mathrm{RuO_2}$) has been proposed as an altermagnetic candidate, although its magnetic ground state remains controversial. Here, we probe weak interfacial magnetic states at the surface of (001)-oriented $\mathrm{RuO_2}$ films using the magnetic proximity effect (MPE) in a van der Waals heterostructure consisting of monolayer tungsten diselenide ($\mathrm{WSe_2}$) atop $\mathrm{RuO_2}$. Temperature-dependent magneto-optical spectroscopy reveals an anomalous excitonic energy shift and a deviation from conventional Varshni behavior below 55 K that are absent in an encapsulated $\mathrm{WSe_2}$ control sample. The anomalous shift reverses sign upon field cooling with opposite magnetic field polarity, indicating a magnetic origin. Polarization-resolved measurements further show a nearly field-independent and fluctuating valley splitting in $\mathrm{WSe_2 / RuO_2}$ in strong contrast to the conventional linear Zeeman splitting observed in the control bare $\mathrm{WSe_2}$ sample. These results suggest that the valley states are governed predominantly by interfacial exchange fields associated with weak surface magnetic states in $\mathrm{RuO_2}$, which do not produce a conventional linear Zeeman response within the applied magnetic field range. Importantly, this approach enables direct optical probing of emergent surface magnetism without introducing an additional ferromagnetic layer, positioning MPE-based optical probing as a tool for investigating weak surface magnetism and offering new possibilities for studying magnetic materials with controversial magnetic states.

2606.20261 2026-06-19 cond-mat.soft 新提交

Activity driven buckling and pattern formation in shells of oriented solids

定向固体壳中的活动驱动屈曲与图案形成

Niels de Graaf Sousa, Varun Venkatesh, Amin Doostmohammadi

AI总结 研究嵌入定向有序粒子的可变形弹性表面壳,发现活动应力驱动新屈曲失稳和非线性图案,线性稳定性分析揭示模式由向列取向和活动符号选择,非线性模拟发现菱形图案和动态状态。

Comments 7 pages, 2 figures

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AI中文摘要

我们研究了活动定向固体壳,即定向有序活动粒子嵌入可变形弹性表面的材料。聚焦圆柱几何,我们表明活动应力驱动了一类在被动壳中不存在的新屈曲失稳和非线性图案。线性稳定性分析揭示,不稳定的屈曲模式由向列取向和活动符号选择,导致轴向、周向和螺旋变形。值得注意的是,由于缺乏拉伸成本,周向模式在任意小的活动下变得不稳定。线性稳定性分析的结果通过全非线性模拟得到证实,进一步揭示了稳定的菱形图案和持续动态状态,包括振荡、传播畴壁和传播波。我们的结果确立了活动定向固体材料壳中的基本屈曲模式和涌现图案,对活动生物组织和工程响应材料具有潜在意义。

英文摘要

We investigate shells of active oriented solid, materials in which orientationally ordered active particles are embedded in a deformable elastic surface. Focusing on cylindrical geometries, we show that active stresses drive a new class of buckling instabilities and nonlinear patterns absent in passive shells. Linear stability analysis reveals that the unstable buckling mode is selected by the nematic orientation and activity sign, leading to axial, circumferential, and helical deformations. Remarkably, circumferential modes become unstable at arbitrarily small activity due to the absence of stretching costs. The results of the linear stability analysis are corroborated by full nonlinear simulations, which further uncover steady diamond shaped patterns and persistent dynamical states including oscillations, traveling domain walls, and propagating waves. Our results establish fundamental buckling modes and emergent patterns in shells of active oriented solid materials, with potential relevance to active biological tissues and engineered responsive materials.

2606.20260 2026-06-19 cond-mat.str-el 新提交

Effects of nonlocal interactions on s- and d-wave superconducting correlations in the extended Hubbard model

扩展Hubbard模型中非局域相互作用对s波和d波超导关联的影响

Pavol Farkasovsky

AI总结 利用Lanczos精确对角化和投影量子蒙特卡洛模拟,研究扩展Hubbard模型中非局域相互作用(如最近邻库仑、关联跳跃、交换和配对跳跃)对s波和d波超导配对关联的影响,发现不同相互作用对称性地增强或抑制特定配对通道。

Comments 21 pages, 7 figures

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AI中文摘要

我们研究了非局域相互作用对扩展Hubbard模型中超导关联的影响。除了在位库仑相互作用和最近邻跳跃外,我们还包含了次近邻跳跃以及几个物理相关的非局域项,即最近邻库仑相互作用、关联跳跃、交换相互作用和配对跳跃。使用$4\ imes4$团簇上的Lanczos精确对角化,并结合选定参数区域上的投影量子蒙特卡洛模拟,我们分析了s波和d波通道中的配对关联。我们证明非局域相互作用对超导关联具有高度非平凡且依赖于对称性的影响。而在位排斥与次近邻跳跃合作增强了d波配对倾向,关联跳跃和最近邻库仑相互作用则强烈促进s波关联,而交换和配对跳跃相互作用可以在超过相对较小的临界强度后有效抑制超导。当同时考虑所有非局域相互作用时,得到的相图揭示了不同配对对称性之间的复杂相互作用和竞争。我们的结果突出了扩展相互作用在塑造强关联系统配对景观中的关键作用,并表明超越最小Hubbard模型的全面处理对于非常规超导的现实描述至关重要。

英文摘要

We investigate the influence of nonlocal interactions on superconducting correlations within the extended Hubbard model. In addition to the on-site Coulomb interaction and nearest-neighbor hopping, we include next-nearest-neighbor hopping together with several physically relevant nonlocal terms, namely nearest-neighbor Coulomb interaction, correlated hopping, exchange interaction, and pair hopping. Using Lanczos exact diagonalization on a $4\times4$ cluster, supported by projector quantum Monte Carlo simulations for selected parameter regimes, we analyze pairing correlations in both the s- and d-wave channels. We demonstrate that nonlocal interactions exert a highly nontrivial and symmetry-dependent influence on superconducting correlations. While the on-site repulsion in cooperation with next-nearest-neighbor hopping enhances d-wave pairing tendencies, correlated hopping and nearest-neighbor Coulomb interaction strongly promote s-wave correlations, whereas exchange and pair-hopping interactions can efficiently suppress superconductivity beyond relatively small critical strengths. When all nonlocal interactions are considered simultaneously, the resulting phase diagrams reveal a complex interplay and competition between different pairing symmetries. Our results highlight the crucial role of extended interactions in shaping the pairing landscape of strongly correlated systems and demonstrate that a comprehensive treatment beyond the minimal Hubbard model is essential for a realistic description of unconventional superconductivity.

2606.20259 2026-06-19 cond-mat.supr-con 新提交

Majorana modes in helical altermagnet without net magnetism and spin-orbit coupling

无净磁性和自旋轨道耦合的螺旋交变磁体中的马约拉纳模式

Xing-Jian Yi, Yue Mao, Cheng-Ming Miao, Qing-Feng Sun

AI总结 提出在螺旋交变磁体表面的一维金属纳米线中实现拓扑超导和马约拉纳束缚态,无需传统自旋轨道耦合和净磁性,通过规范变换揭示螺旋框架诱导自旋动量锁定,交变磁性打破时间反演对称性。

Journal ref Phys. Rev. B 113, L060408 (2026)

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AI中文摘要

我们提出了一种方案,在螺旋交变磁体表面的一维金属纳米线中,通过与s波超导体邻近,实现拓扑超导和马约拉纳束缚态(MBSs),消除了对传统自旋轨道耦合和净磁性的需求。通过规范变换,我们证明螺旋框架自然诱导自旋动量锁定,而交变磁性打破时间反演对称性。拓扑超导相可通过化学势、交变磁体强度和螺旋频率很好地调节。此外,我们的输运计算结果揭示了量子化电导特征:纳米线末端的2e^2/h零偏压峰和具有相反手性的纳米线畴壁处的4e^2/h隧穿电导,分别通过金属引线和扫描隧道显微镜检测。我们的研究为寻找MBSs提供了新视角。

英文摘要

We propose a scheme to realize topological superconductor and Majorana bound states (MBSs) in a one-dimensional metal nanowire on the surface of a helical altermagnet and in proximity to an s-wave superconductor, removing the requirement of conventional spin-orbit coupling and net magnetism. Through gauge transformation, we demonstrate that the helical frame naturally induces spin-momentum locking while the altermagnetism breaks time-reversal symmetry. The topological superconducting phase is well tuned by chemical potential, altermagnet strength, and helical frequency. Besides, our transport calculation results reveal quantized conductance signatures: a 2e2/h zero-bias peak at nanowire ends and a 4e2/h tunneling conductance at the domain wall of nanowires with opposite chirality, detected via metal lead and scanning tunneling microscopy, respectively. Our research offers new perspectives on finding MBSs.

2606.20253 2026-06-19 cond-mat.mtrl-sci cs.CE 新提交

On representation of macroscopic crack in periodic fine-scale discrete mechanical models

关于周期性细观离散力学模型中宏观裂纹的表征

Jan Raisinger, Jan Eliáš

AI总结 针对异质软化材料多尺度模拟中边界条件影响应变局部化的问题,评估了新型边界条件(如镶嵌、渗流路径对齐及带位移跳跃的球形周期边界)在细观离散粒子模型中的适用性,发现镶嵌边界条件能稳定产生由模型几何唯一确定的局部化带。

Comments 28 pages, 20 figures

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AI中文摘要

在异质软化材料的多尺度建模中,细观模型的边界条件强烈影响应变局部化模式和宏观响应。对于直线型模型(如正方形或立方体),当局部化带倾角与周期方向不匹配时,标准周期边界条件会产生人为的延性行为并导致过度能量耗散。最近提出的镶嵌和渗流路径对齐边界条件通过调整周期框架以与演化的局部化带对齐,有望解决这一问题。另外,球形/圆形模型通过设计提供与方向无关的响应。不幸的是,标准周期边界条件不允许在球形模型边界上形成适当的局部化带交叉。最近的一项修改通过在球形周期边界条件中添加位移跳跃来解决这一问题。本研究评估了这些新型边界条件在混凝土细观离散粒子模型中的适用性。分析了不同加载方向下受单轴拉伸的二维正方形和圆形模型,并将所选方法扩展到三维立方体模型。结果表明,渗流路径对齐边界条件存在主要缺陷:由于两个边界部分的应变不均匀,可能导致多条局部化带,且其弱约束部分容易产生虚假应变局部化。相比之下,镶嵌边界条件始终产生定义明确的局部化带,其长度仅由模型几何决定,使得在后处理中易于考虑。对圆形模型应用带位移跳跃的周期边界条件有时会错误地产生与标准周期边界条件相似的裂纹模式。

英文摘要

In multiscale modeling of heterogeneous softening materials, boundary conditions (BC) in the fine-scale model strongly influence the strain localization pattern and the macroscopic response. For rectilinear models (e.g., squares or cubes), standard Periodic BCs produce artificially ductile behavior with excessive energy dissipation when the localization band inclination does not match the periodicity directions. Recently proposed Tessellation and Percolation-path-aligned BCs promise to address this by adapting the periodicity frame to align with the evolving localization bands. Alternatively, spherical/circular models provide an orientation independent response by design. Unfortunately, the standard Periodic BCs do not allow development of proper localization band crossing spherical model's boundaries. A recently proposed modification addresses this by adding a displacement jump to the spherical periodic BCs. This study evaluates the applicability of these novel BCs to a mesoscale discrete particle model of concrete. Two-dimensional square and circular models under uniaxial tension with different loading directions are analyzed, with the selected approaches extended to three-dimensional cube models. Results show that Percolation-path-aligned BCs exhibit major shortcomings: they can lead to multiple localization bands due to uneven straining of the two boundary sections and their weakly constrained section can be prone to spurious strain localization. In contrast, Tessellation BCs consistently yield a well-defined localization band, whose length is determined solely by the model geometry, making it straightforward to account for in post-processing. Periodic boundary conditions augmented with a displacement jump applied to a circular model sometimes incorrect produce crack patterns similar to those under the standard Periodic BCs.

2606.20190 2026-06-19 cond-mat.soft 新提交

Independent Control of Transport and Order in a Ratcheted Colloidal Suspension

棘轮胶体悬浮液中输运与有序性的独立控制

Sudipta Mandal, Dipanjan Chakraborty, Debasish Chaudhuri

AI总结 通过大规模分子动力学模拟,研究随机非对称分段线性闪烁棘轮驱动的二维排斥相互作用胶体悬浮液中的定向输运,发现频率和不对称性可独立控制粒子流,分别影响结构有序性。

Comments 18 pages

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AI中文摘要

我们通过大规模分子动力学模拟,研究了由随机非对称分段线性闪烁棘轮驱动的二维排斥相互作用胶体悬浮液中的定向输运。驱动频率和棘轮不对称性提供了两种独立控制粒子流的方式,但它们对悬浮液的影响不同。在固定不对称性下,粒子流显示出与棘轮频率的共振,该共振由相互作用粒子的集体弛豫动力学决定。由此产生的输运增强伴随着缺陷介导的结构变化,显示出密度依赖的六角相和类固态,较大的电流通常与较弱的有序性相关。相比之下,在固定频率下,改变棘轮不对称性主要改变定向偏置的强度,可以显著增强电流,同时六角有序性基本不变。在平衡六角-熔化区域附近,这使得在不严重破坏六重取向有序性的情况下产生显著的定向电流成为可能。这些结果表明,频率调谐将输运与结构重组耦合,而不对称性调谐主要控制输运而结构基本不变,为操控驱动胶体悬浮液中的输运和有序性提供了不同且互补的途径。

英文摘要

We study directed transport in a two-dimensional suspension of repulsively interacting colloids driven by a stochastic asymmetric piecewise-linear flashing ratchet using large-scale molecular dynamics simulations. The driving frequency and the ratchet asymmetry offer two independent ways of controlling the particle current, but they affect the suspension differently. At fixed asymmetry, the current shows a resonance with ratcheting frequency that is set by the collective relaxation dynamics of the interacting particles. The resulting increase in transport is accompanied by defect-mediated structural changes, showing density-dependent hexatic and solid-like states, with larger currents generally associated with weaker ordering. By contrast, at fixed frequency, changing the ratchet asymmetry mainly alters the strength of the directed bias and can significantly enhance the current while leaving the hexatic order largely unchanged. Near the equilibrium hexatic-melting regime, this makes it possible to generate substantial directed currents without strongly disrupting sixfold orientational order. These results show that frequency tuning couples transport to structural reorganization, whereas asymmetry tuning primarily controls transport leaving the structure largely unaltered, providing distinct and complementary routes for manipulating transport and order in driven colloidal suspensions.

2606.20187 2026-06-19 cond-mat.dis-nn quant-ph 新提交

Truncated Wigner dynamics of biclique quantum spin glasses

双团簇量子自旋玻璃的截断维格纳动力学

Dries Sels

AI总结 研究双团簇量子自旋玻璃的近绝热动力学,使用离散截断维格纳近似(TWA)方法,在较大系统尺寸下高保真度恢复样本波动和临界指数,计算成本低,可扩展至数万量子比特。

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AI中文摘要

量子自旋玻璃常被视为研究量子优化算法的试验平台,并因此成为各种量子优势主张的主题。本文在(离散)截断维格纳近似(TWA)框架下研究双团簇量子自旋玻璃的近绝热动力学。小系统基准测试表明,在广泛的退火时间范围内,TWA 能够恢复 Edwards-Anderson 序参量的样本间波动,且随着系统尺寸增大保真度提高。我们根据理论预期从 Binder 累积量中提取临界指数,重现了最近的量子实验。该方法的计算成本极低,可轻松应用于数万个量子比特。

英文摘要

Quantum spin glasses are often considered testbeds for studying quantum optimization algorithms and as such have been the subject of various quantum advantage claims. Here we investigate the near adiabatic dynamics of biclique quantum spin glasses within the (discrete) truncated Wigner approximation (TWA). Benchmarks on small systems show that TWA recovers sample-to-sample fluctuations of the Edwards-Anderson order parameter, over a wide range of annealing times, with increasing fidelity when the system size increases. We extract critical exponents from the Binder cumulant in line with theoretical expectations, reproducing recent quantum experiments. The computational cost of the method is minimal and it can easily be applied to tens of thousands of qubits.

2606.20182 2026-06-19 cond-mat.str-el 新提交

Anomalous Transverse Response in Nodal line Semimetal Mn$_{3}$SnC

节点线半金属Mn$_{3}$SnC中的异常横向响应

Sunil Gangwar, C. S. Yadav

AI总结 研究反钙钛矿节点线半金属Mn$_{3}$SnC中异常霍尔效应和异常能斯特效应的机制,发现其由本征贝里曲率主导,并建立了统一关系。

Comments 7 pages, 3 figures

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AI中文摘要

拓扑表面态与磁性的相互作用产生了非常规输运行为,如异常霍尔效应(AHE)和异常能斯特效应(ANE)。反钙钛矿如Mn$_{3}$SnC,作为节点线半金属并同时表现出反铁磁(AFM)和铁磁(FM)有序,为异常输运现象提供了肥沃的土壤。在这里,我们报告了该化合物中的异常输运(AHE和ANE)主要由本征贝里曲率效应控制。我们利用Mott关系建立了AHE和ANE之间的统一关系。异常能斯特信号中体现了AFM和FM磁振子对电子的散射。异常能斯特电导率与异常霍尔电导率之比$|\alpha^A_{xy}|/\sigma^A_{xy}$占据了$k_B/e$的相当大一部分,表明贝里曲率对ANE有强烈贡献。

英文摘要

The interplay of topological surface states and magnetism gives rise to unconventional transport behaviors such as the anomalous Hall effect (AHE) and anomalous Nernst effect (ANE). Antiperovskites such as Mn$3$SnC, which are nodal-line semimetals and exhibit concurrent antiferromagnetic (AFM) and ferromagnetic (FM) ordering, provide a fertile ground for anomalous transport phenomena. Here, we report that the anomalous transport (AHE and ANE) in this compound is predominantly governed by the intrinsic Berry-curvature effect. We establish a unified relationship between the AHE and ANE using Mott's relation. Electron scattering by both AFM and FM magnons is manifested in the anomalous Nernst signal. The ratio of the anomalous Nernst conductivity to the anomalous Hall conductivity, $|α^A{xy}|/σ^A_{xy}$, constitutes a sizable fraction of $k_B/e$, indicating a strong Berry-curvature contribution to the ANE.

2606.20178 2026-06-19 cond-mat.mtrl-sci physics.comp-ph 新提交

Large spin splitting at ferromagnetic surfaces of bulk antiferromagnets

块体反铁磁体铁磁表面的大自旋分裂

William A. Schaarman, Sophie F. Weber

AI总结 利用密度泛函理论和模型哈密顿量,揭示块体反铁磁体低对称性铁磁表面能带的大自旋分裂,提出通过表面对称性破缺在反铁磁体中实现功能性大自旋分裂的新途径。

Comments 5 pages, 4 figures without appendix. To be submitted to Physical Review Letters

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AI中文摘要

我们使用密度泛函理论和模型哈密顿量揭示了块体反铁磁体(AFM)的低对称性、铁磁表面上能带的大自旋分裂。目前,人们对于寻找结合了反铁磁体的鲁棒性和超快动力学以及通常仅限于铁磁体的大功能性自旋分裂的新材料平台有着极大的兴趣。在这里,我们展示了一类具有对称性允许磁化的反铁磁表面可以通过亚晶格分辨交换分裂的体简并提升来承载大自旋分裂。使用模型哈密顿量,我们表明自旋分裂对于两种铁磁表面结构最大化:具有单个未补偿磁亚晶格的终止面,以及在体相中磁性和电子补偿但在表面截断时获得不同晶体场环境的双亚晶格表面。后一种情况可以产生类似铁磁体的自旋分裂幅度,同时具有可忽略的小未补偿磁化。相比之下,当表面磁化来自对称连接的亚晶格上的相对论性倾斜时,自旋分裂预计很小。我们通过$\mathrm{Cr_2O_3}$和$\mathrm{FeF_2}$的第一性原理计算证实了这些预测,发现分裂范围从$\sim10\mathrm{meV}$到$\sim1\mathrm{eV}$,具体取决于所研究的表面。我们的发现表明,固有的表面对称性破缺是在更广泛的反铁磁材料中实现大功能性自旋分裂的一条途径。

英文摘要

We use density functional theory and model Hamiltonians to reveal large spin splitting of bands localized at low-symmetry, ferromagnetic surfaces of bulk antiferromagnets (AFMs). There is great interest in finding new material platforms combining the robustness and ultrafast dynamics of AFMs with large, functional spin splitting which is often restricted to ferromagnets. Here, we show that a subset of AFM surfaces which have symmetry-allowed magnetization can host large spin splitting via bulk degeneracy lifting of sublattice-resolved exchange splittings. Using model Hamiltonians, we show that the spin splitting is maximized for two ferromagnetic surface motifs: terminations with single uncompensated magnetic sublattices, and two-sublattice surfaces whose sublattices are magnetically and electronically compensated in the bulk, but acquire distinct crystal field environments via surface truncation. The latter case can yield FM-like spin splitting magnitudes while also having vanishingly small uncompensated magnetization. In contrast, when surface magnetization arises from relativistic canting on symmetry-connected sublattices, the spin splitting is expected to be small. We confirm these predictions with first-principles calculations of $\mathrm{Cr_2O_3}$ and $\mathrm{FeF_2}$, finding splittings from $\sim10\mathrm{meV}$-$\sim1\mathrm{eV}$ depending on the surface in question. Our findings point to intrinsic surface symmetry breaking as a route to large, functional spin splitting in an expanded range of AFM materials.

2606.20170 2026-06-19 cond-mat.mes-hall cond-mat.str-el cond-mat.supr-con 新提交

Transient triplet blockade in Andreev junction

安德烈夫结中的瞬态三重态阻塞

R. Taranko, J. Baranski, A. Jankiewicz, K. Wrzesniewski, I. Weymann, T. Domanski

AI总结 研究超导体-量子点-量子点-正常金属结中非平衡三重态配置的瞬态形成及其对亚隙电荷输运的阻塞效应,通过解析和数值计算揭示其时间演化尺度。

Comments 15 pages, 13 figures

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AI中文摘要

我们研究了在超导体和正常金属引线之间串联两个量子点的纳米结中,非平衡条件下出现的时间依赖三重态配置。我们表明,当两个量子点被相同自旋电子单占据时,点内电子配对被抑制,这显著影响了亚隙电荷输运。我们研究了这种配置可以暂时遇到的过程,无论是由于初始条件还是通过施加外部磁场。我们的解析和数值计算提供了时间尺度的估计,表征了三重态配置的演化,这可以在时间分辨隧穿测量中显现。这种三重态配置的非平衡特征可能与超导量子比特的操作相关,无论是常规实现还是拓扑实现。

英文摘要

We study the time-dependent triplet configuration, appearing under nonequilibrium conditions in a nanoscopic junction with two quantum dots coupled in series between superconductor and normal metallic lead. We show that in the situation, when both quantum dots are singly occupied by identical spin electrons, the on-dot electron pairing is suppressed what substantially affects the subgap charge transport. We investigate processes in which such configuration can be temporarily encountered, either due to the initial conditions or by imposing the external magnetic field. Our analytical and numerical calculations provide estimations for the temporal scales, characterizing evolution of the triplet configuration which could be manifested in the time-resolved tunneling measurements. Such nonequilibrium features of the triplet configuration might be relevant to operations on superconducting qubits, in their conventional and/or topological realizations.

2606.20168 2026-06-19 cond-mat.stat-mech cond-mat.str-el hep-th math-ph math.MP 新提交

Norms, overlaps and Yangian descendants for the Haldane--Shastry spin chain

Haldane-Shastry自旋链的范数、重叠和Yangian后代

Yunfeng Jiang, Jules Lamers, Yuan Miao

AI总结 本文通过代数Bethe ansatz系统构造了Haldane-Shastry自旋链的Yangian后代态,并推导了这些态的范数和重叠的乘积与行列式公式。

Comments 34 pages, 3 figures

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AI中文摘要

Haldane-Shastry自旋链是一个具有长程相互作用的原型可积模型,以其承载分数统计准粒子和作为共形场论的离散类似物而著称。其显著的简单性与完整的Yangian自旋对称性密切相关。尽管该对称性的最高权态已知,但计算各种物理量所需的后代态的系统处理仍不完整。在这项工作中,我们遵循Ferrando等人最近的工作,通过代数Bethe ansatz提供了这些后代态的详细构造。在极端扭曲极限下,它包含了Gelfand-Tsetlin基。作为应用,我们推导了这些态的范数和重叠的乘积与行列式公式。

英文摘要

The Haldane-Shastry spin chain is a prototypical integrable model with long-range interactions, notable for hosting quasiparticles with fractional statistics and serving as a discrete analogue of a conformal field theory. Its remarkable simplicity is closely tied to a full Yangian spin symmetry. While the highest-weight states for this symmetry are known explicitly, a systematic treatment of the descendant states, needed for the computation of various physical quantities, has remained incomplete. In this work, we provide a detailed construction of these descendants in terms of the algebraic Bethe ansatz following recent work of Ferrando et al. In the limit of extreme twist, it includes the Gelfand-Tsetlin basis. As an application, we derive product and determinant formulae for norms and overlaps of these states.

2606.20159 2026-06-19 cond-mat.mes-hall cond-mat.mtrl-sci 新提交

Electric-field-driven magnetic switching and tightly bound interlayer excitons in bilayer CrSBr

电场驱动的磁开关与双层CrSBr中的强束缚层间激子

Xiubin Li, Yu Sun, Xuanji Wang, Chunyan Wang, Kenji Watanabe, Takashi Taniguchi, Sheng Liu, Ting Yu, Liang Li, Tao Zhang, Jing Li

AI总结 本研究在双层CrSBr中实现了电场驱动的反铁磁-铁磁可逆开关,并发现强束缚层间激子,揭示了线性磁电效应和电场调制的层间交换耦合两种共存机制。

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AI中文摘要

在二维范德华磁体中实现电场控制磁序是低功耗自旋技术的一个核心目标。在环境稳定的反铁磁体CrSBr中,强磁各向异性和稳健的激子-自旋耦合提供了有利平台,但其磁相的电学确定性控制尚未实现。这里我们展示了在无有意载流子掺杂的双栅极双层CrSBr中,电场驱动的反铁磁与铁磁态之间的可逆开关。同时,光致发光测量解析出一个强束缚的层间激子,其本征偶极矩仅为约1 e埃。磁相变的电场依赖性揭示了两种共存机制:反铁磁态中的线性磁电效应和电场调制的层间交换耦合。它们的相互作用解释了临界磁场的非对称演化。我们的结果确立了双层CrSBr作为电控自旋光电子功能器件的有前途的二维材料。

英文摘要

Electric field control of magnetic order in two-dimensional (2D) van der Waals magnets is a central goal for low-power spin-based technologies. In the ambient-stable antiferromagnet CrSBr, strong magnetic anisotropy and robust exciton-spin coupling provide a favorable platform, yet deterministic electric field control of its magnetic phases has not been achieved. Here we demonstrate electric-field-driven reversible switching between antiferromagnetic and ferromagnetic states in dual-gated bilayer CrSBr without intentional carrier doping. In parallel, photoluminescence measurements resolve a tightly bound interlayer exciton with an intrinsic dipole moment of only ~1 e angstrom. The electric field dependence of the magnetic phase transition reveals two coexisting mechanisms: a linear magnetoelectric effect in the antiferromagnetic state and an electric-field-modulated interlayer exchange coupling. Their interplay accounts for the asymmetric evolution of the critical magnetic field. Our results establish bilayer CrSBr as a promising 2D material for electrically controlled spin-optoelectronic functionalities.