非线性科学
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- [1] arXiv:2511.14370 [中文pdf, pdf, html, 其他]
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标题： 由时变耦合函数引起的振荡阻尼标题： Oscillation Quenching Induced By Time-Varying Coupling Functions评论： 被接受于混沌：非线性科学跨学科期刊主题： 适应性与自组织系统 (nlin.AO) ; 计算物理 (physics.comp-ph) ; 数据分析、统计与概率 (physics.data-an)
自然和人造系统的振荡动力学可能因其时变相互作用而被破坏，导致振荡抑制现象，其中振荡被抑制。 我们引入了一个框架，用于分析、评估和控制通过耦合函数引起的振荡抑制。 具体来说，通过观察极限环振荡器，我们研究了时变扩散和周期性耦合函数引起的分岔和动态转变。 我们在保持耦合强度不变的情况下，研究了由耦合函数时变形式引起的振荡抑制状态之间的转变。 时变周期性耦合函数使我们能够识别出之前未报告过的新颖、非平凡的非均匀状态。 此外，通过使用动态贝叶斯推断，我们还开发了一个比例积分（PI）控制器，该控制器能够维持振荡和\red{prevents oscillation quenching from occurring}。 除了当前的实现及其推广，该框架对于在受到时变相互作用的广泛系统中识别和控制振荡抑制具有更广泛的含义。
The oscillatory dynamics of natural and man-made systems can be disrupted by their time-varying interactions, leading to oscillation quenching phenomena in which the oscillations are suppressed. We introduce a framework for analyzing, assessing, and controlling oscillation quenching using coupling functions. Specifically, by observing limit-cycle oscillators we investigate the bifurcations and dynamical transitions induced by time-varying diffusive and periodic coupling functions. We studied the transitions between oscillation quenching states induced by the time-varying form of the coupling function while the coupling strength is kept invariant. The time-varying periodic coupling function allowed us to identify novel, non-trivial inhomogeneous states that have not been reported previously. Furthermore, by using dynamical Bayesian inference we have also developed a Proportional Integral (PI) controller that maintains the oscillations and \red{prevents oscillation quenching from occurring}. In addition to the present implementation and its generalizations, the framework carries broader implications for identification and control of oscillation quenching in a wide range of systems subjected to time-varying interactions.
- [2] arXiv:2511.00044 [中文pdf, pdf, html, 其他]
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标题： ReLaX-Net：用于参数高效物理神经网络的层重用标题： ReLaX-Net: Reusing Layers for Parameter-Efficient Physical Neural Networks主题： 机器学习 (cs.LG) ; 适应性与自组织系统 (nlin.AO)
物理神经网络（PNN）是下一代计算系统的有前景的平台。 然而，最近数字神经网络性能的提升主要得益于可训练参数数量的快速增长，而迄今为止展示的PNN在规模上仍落后几个数量级。 这反映了早期数字神经网络中发现的规模和性能限制。 在那个时期，参数的有效重用促进了参数高效架构的发展，如卷积神经网络。 在这项工作中，我们数值研究了针对PNN的硬件友好的权重绑定。 关键的是，对于许多PNN系统，在前向传递的快速动态活动元件和仅缓慢可训练的实现权重和偏差的元件之间存在时间尺度分离。 考虑到这一点，我们提出了用于扩展神经网络的层重用（ReLaX-Net）架构，该架构采用简单的逐层时间复用方案来增加有效网络深度并高效利用参数数量。 我们只需要为现有的PNN添加快速开关。 我们通过在图像分类和自然语言处理任务上的数值实验验证了ReLaX-Nets。 我们的结果表明，ReLaX-Net仅对传统PNN进行微小修改即可提高计算性能。 我们观察到有利的扩展性，即ReLaX-Nets在相同参数数量的情况下超越了等效的传统RNN或DNN的性能。
Physical Neural Networks (PNN) are promising platforms for next-generation computing systems. However, recent advances in digital neural network performance are largely driven by the rapid growth in the number of trainable parameters and, so far, demonstrated PNNs are lagging behind by several orders of magnitude in terms of scale. This mirrors size and performance constraints found in early digital neural networks. In that period, efficient reuse of parameters contributed to the development of parameter-efficient architectures such as convolutional neural networks. In this work, we numerically investigate hardware-friendly weight-tying for PNNs. Crucially, with many PNN systems, there is a time-scale separation between the fast dynamic active elements of the forward pass and the only slowly trainable elements implementing weights and biases. With this in mind,we propose the Reuse of Layers for eXpanding a Neural Network (ReLaX-Net) architecture, which employs a simple layer-by-layer time-multiplexing scheme to increase the effective network depth and efficiently use the number of parameters. We only require the addition of fast switches for existing PNNs. We validate ReLaX-Nets via numerical experiments on image classification and natural language processing tasks. Our results show that ReLaX-Net improves computational performance with only minor modifications to a conventional PNN. We observe a favorable scaling, where ReLaX-Nets exceed the performance of equivalent traditional RNNs or DNNs with the same number of parameters.
- [3] arXiv:2503.19761 [中文pdf, pdf, html, 其他]
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标题： 跨利夫希茨转变的涌现对密度波序标题： Emergent Pair Density Wave Order Across a Lifshitz Transition主题： 强关联电子 (cond-mat.str-el) ; 超导性 (cond-mat.supr-con)
我们通过关注不同参数区域中的动量分辨谱，数值研究了Kondo-Heisenberg链中配对密度波序（PDW）的特征迹象。 密度矩阵重整化群计算表明，该相由具有两个极小值和四个费米点的色散关系表征，表明有效最近邻跃迁的出现，这是为了避免磁性挫折的二阶效应。 在谱中，这些成对态表现为能隙内的束缚态，其权重集中在空穴口袋中。 低能物理可以通过包含最近邻跃迁的广义t-J模型来理解。 我们的结果为寻找实验特征和其他可以实现PDW物理的模型提供了指导。
We numerically investigate the telltale signs of pair-density-wave order (PDW) in the Kondo-Heisenberg chain by focusing on the momentum resolved spectrum in different parameter regimes. Density matrix renormalization group calculations reveal that this phase is characterized by a dispersion with two minima and four Fermi points, indicating the emergence of an effective next-nearest-neighbor hopping that arises as a second-order effect to avoid magnetic frustration. The pairs appear in the spectrum as in-gap bound states with weight concentrated in the hole pockets. The low-energy physics can be understood by means of a generalized t-J model with next-nearest-neighbor hopping. Our results offer a guide for searching for experimental signatures, and for other models that can realize PDW physics.
新提交 (展示 3 之 3 条目 )
- [4] arXiv:2502.00659 (交叉列表自 physics.flu-dyn) [中文pdf, pdf, html, 其他]
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标题： 能量、涡量和螺旋度在聚合物湍流中的传递标题： Energy, enstrophy and helicity transfers in polymeric turbulence主题： 流体动力学 (physics.flu-dyn) ; 混沌动力学 (nlin.CD)
我们通过直接数值模拟来表征均匀各向同性聚合物湍流中能量、涡量和螺旋度的逐尺度传输。微尺度雷诺数设为$Re_λ\approx 460$，德鲍数量$De = τ_p/τ_f$在$1/9 \le De \le 9$之间变化；$τ_p$是聚合物的松弛时间，$τ_f$是流动最大尺度的周转时间。该研究依赖于能量、涡量和螺旋度的精确逐尺度预算方程（由控制模型方程推导而来），这些方程考虑了聚合物对流动的反作用。聚合物在流动中起到汇或源的作用，并为这三个量的逐尺度传输提供了替代途径，其相关性随着$De$而变化。我们发现，聚合物主要在较小尺度上消耗非线性能量级联，通过削弱极端正向以及反向局部事件。对于$De \ge 1$，新的聚合物驱动的能量通量在小尺度上占主导地位，并平均地将能量从较大尺度传输到较小尺度，伴有局部的逆散射事件。 聚合物通过使涡度拉伸减弱，而涡量主要由流体-聚合物相互作用产生，尤其是在$De \ge 1$时。 因此，对小尺度流动拓扑的检查显示，聚合物倾向于二维应变状态的事件，并促进/抑制极端拉伸/旋转事件：在聚合物湍流中，剪切和平面扩展流动更有可能发生。 在最大尺度注入的螺旋度表现出与能量相似的传输过程，主要由大尺度的非线性级联驱动，并由小尺度的聚合物驱动通量。 发现聚合物倾向于破坏小尺度镜像对称性的事件，相对螺旋度在所有尺度上随着$De$的增加而单调增加。
We characterise the scale-by-scale transfers of energy, enstrophy and helicity in homogeneous and isotropic polymeric turbulence using direct numerical simulations. The microscale Reynolds number is set to $Re_λ\approx 460$, and the Deborah number $De = τ_p/τ_f$ is varied between $1/9 \le De \le 9$; $τ_p$ is the polymeric relaxation time and $τ_f$ is the turnover time of the largest scales of the flow. The study relies on the exact scale-by-scale budget equations (derived from the the governing model equations) for energy, enstrophy and helicity, which account for the back-reaction of the polymers on the flow. Polymers act as a sink/source in the flow, and provide alternative routes for the scale-by-scale transfers of the three quantities, whose relevance changes with $De$. We find that polymers deplete the nonlinear energy cascade mainly at smaller scales, by weakening both the extreme forward as well as reverse local events. The new polymer-driven energy flux dominates at small scales for $De \ge 1$, and on average transfers energy from larger to smaller scales with localised backscatter events. Polymers weaken the stretching of vorticity with the enstrophy being mainly generated by the fluid-polymer interaction, especially when $De \ge 1$. Accordingly, an inspection of the small-scale flow topology shows that polymers favour events with two-dimensional state of straining, and promote/inhibit extreme extension/rotation events: in polymeric turbulence shear and planar extensional flows are more probable. The helicity injected at the largest scales shows a similar transfer process to as energy, being mainly driven by the nonlinear cascade at large scales and by the polymer-driven flux at small scales. Polymers are found to favour events that break the small-scale mirror symmetry, with the relative helicity monotonically increasing with $De$ at all scales.
- [5] arXiv:2511.14678 (交叉列表自 cond-mat.mtrl-sci) [中文pdf, pdf, html, 其他]
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标题： 硅中飞秒隧穿电离的巨增强与无序驱动的退相干相竞争标题： Giant enhancement of attosecond tunnel ionization competes with disorder-driven decoherence in siliconMahmoud Jalali Mehrabad, Alireza Parhizkar, Lida Xu, Gregory Moille, Avik Dutt, Dirk Englund, Kartik Srinivasan, Daniel Leykam, Mohammad Hafezi主题： 材料科学 (cond-mat.mtrl-sci)
高次谐波产生（HHG）是一种强场现象，对固体中电子-空穴对的隧穿电离和相干传输的阿托秒动力学非常敏感。 尽管固体HHG的基础已经确立，但对亚周期时间尺度上退相干本质的深入理解仍然难以捉摸。 此外，对在纳米尺度上控制电离的工具需求日益增加。 在这里，我们研究了沿晶体到非晶（c-Si到a-Si）结构相变的硅中的HHG，并观察到光谱的显著重塑，低阶谐波产率增强，而高阶谐波则被抑制。 模拟实空间量子动力学将我们的观察与非晶相中隧穿电离产率的巨大增强（>250倍）以及由无序引起的退相干联系起来，这种退相干在大约六个晶格位点内阻尼了电子-空穴极化。 HHG光谱还揭示了传统探测器未显示的残留有序性。 最后，我们观察到非晶硅岛的快速且有针对性的非共振激光退火。 我们的结果为强场现象中的阿托秒退相干提供了独特的见解，确立了HHG光谱作为结构无序探测工具，并为光波纳米电子学的新机遇铺平了道路。
High-harmonic generation (HHG) is a strong-field phenomenon that is sensitive to the attosecond dynamics of tunnel ionization and coherent transport of electron-hole pairs in solids. While the foundations of solid HHG have been established, a deep understanding into the nature of decoherence on sub-cycle timescales remains elusive. Furthermore, there is a growing need for tools to control ionization at the nanoscale. Here, we study HHG in silicon along a crystalline-to-amorphous (c-Si to a-Si) structural phase transition and observe a dramatic reshaping of the spectrum, with enhanced lower-order harmonic yield accompanied by quenching of the higher-order harmonics. Modelling the real-space quantum dynamics links our observations to a giant enhancement (>250 times) of tunnel ionization yield in the amorphous phase and a disorder-induced decoherence that damps the electron-hole polarization over approximately six lattice sites. HHG spectroscopy also reveals remnant order that was not apparent with conventional probes. Finally, we observe a rapid and targeted non-resonant laser annealing of amorphous silicon islands. Our results offer a unique insight into attosecond decoherence in strong-field phenomena, establish HHG spectroscopy as a probe of structural disorder, and pave the way for new opportunities in lightwave nanoelectronics.
- [6] arXiv:2511.13740 (交叉列表自 math.DS) [中文pdf, pdf, 其他]
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标题： 时变非线性振子中的管可积性标题： Tube Integrability in a Time-Dependent Nonlinear OscillatorHediyeh M. Dinani, Georgios G. Pyrialakos, Abraham M. Berman Bradley, Monika Monika, Huizhong Ren, Mahmoud A. Selim, Ulf Peschel, Demetrios N. Christodoulides, Mercedeh Khajavikhan评论： 25页，13图主题： 动力系统 (math.DS) ; 精确可解与可积系统 (nlin.SI)
我们研究具有时变系数g(t)的非线性振子z'' + omega^2 z + g(t) z^2 = 0。 我们证明，当g(t) = alpha2(t)^(-5/2)且alpha2(t)满足一个非线性的三阶微分方程时，该方程具有精确的二次不变量I(z,p,t)。 由此得到的不变量将动力学限制在扩展相空间(z,p,t)中的一个光滑二维曲面。 如果alpha2(t)是周期性的，这个曲面形成一个紧致的不变环面。 然而，我们表明，alpha2(t)的周期解通常会被一种共振机制所阻碍，从而导致非周期但非混沌的演化。 在这个区域内，不变曲面是非紧致的，并沿着时间方向延伸，形成一个管状结构而不是环面。 因此，我们提出“管可积性”这一术语，用于描述其不变流形在时间上是非紧致的可积系统。 推导了alpha2(t)到三阶的摄动展开式，并与数值积分进行了比较，明确了截断级数提供定量准确近似的参数范围。 对于小y0的级数失效反映了展开式的渐近性质，而不是可积性的丧失。
We study the nonlinear oscillator z'' + omega^2 z + g(t) z^2 = 0 with a time-dependent coefficient g(t). We show that this equation admits an exact quadratic invariant I(z,p,t) provided that g(t) = alpha2(t)^(-5/2) and that alpha2(t) satisfies a nonlinear third-order differential equation. The resulting invariant constrains the dynamics to a smooth two-dimensional surface in the extended phase space (z,p,t). If alpha2(t) is periodic, this surface forms a compact invariant torus. However, we show that periodic solutions of alpha2(t) are generically obstructed by a resonance mechanism, leading instead to an aperiodic but non-chaotic evolution. In this regime the invariant surface is non-compact and extends along the time direction, forming a tube rather than a torus. We therefore propose the term "tube integrability" for integrable systems whose invariant manifolds are non-compact in time. A perturbation expansion for alpha2(t) up to third order is derived and compared with numerical integration, clarifying the parameter regimes in which the truncated series provides quantitatively accurate approximations. The breakdown of the series for small y0 reflects the asymptotic nature of the expansion rather than a loss of integrability.
- [7] arXiv:2509.09209 (交叉列表自 math-ph) [中文pdf, pdf, html, 其他]
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标题： XXZ链在$Δ=-1/2$以及全对称交替符号矩阵标题： The open XXZ chain at $Δ=-1/2$ and totally-symmetric alternating sign matrices评论： 32页，4张图；V2：对定理4.1证明的改进；引用问题的更正主题： 数学物理 (math-ph) ; 统计力学 (cond-mat.stat-mech)
具有各向异性参数$Δ=-\frac12$的开放 XXZ 自旋链，具有依赖于参数$x$的对角边界场和有限长度$N$被研究。 在自然归一化下，其基态矢量的分量是$x$的多项式，系数为整数。 证明了它们的和由一个生成函数给出，该生成函数用于加权枚举完全对称的交替符号矩阵，权重取决于$x$。
The open XXZ spin chain with the anisotropy parameter $Δ=-\frac12$, diagonal boundary fields that depend on a parameter $x$, and finite length $N$ is studied. In a natural normalisation, the components of its ground-state vector are polynomials in $x$ with integer coefficients. It is shown that their sum is given by a generating function for the weighted enumeration of totally-symmetric alternating sign matrices with weights depending on $x$.
- [8] arXiv:2511.13968 (交叉列表自 physics.optics) [中文pdf, pdf, 其他]
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标题： 通过光学热力学的光路由标题： Universal Routing of Light via Optical Thermodynamics期刊参考： 自然光子学（2025）：1-6主题： 光学 (physics.optics) ; 适应性与自组织系统 (nlin.AO)
理解并利用复杂非线性系统的动态特性，如今是众多科学和技术努力的核心。 在光学领域，非线性多模环境中光的演化提出了一个严峻的问题，因为其混沌演化常常阻碍预测性见解。 最近，提出了一种光学热力学框架，该框架可以系统地预测并利用这些系统的复杂行为。 在这项工作中，通过部署熵原理，我们展示了一个反直觉的光学过程，在这个过程中，光被注入到精心设计的非线性阵列的任何输入端口时，都会普遍地进入一个紧密定位的基态，这种响应在线性保守排列中是完全无法实现的。 这一现象源于晶格结构与动能和非线性哈密顿量组件展开方式之间的相互作用，导致了两种光学热力学过程：类似焦耳-汤姆逊膨胀随后是模式热化。 实验上，这种效应在适当配置的非线性时间合成网格晶格中得到了演示，其中光学温度接近零，导致光无论初始激发位置如何都会在一点凝聚。 这里展示的效应为应用光学热力学原理实现新型光学功能开辟了新的途径，例如全光束控制、复用以及高功率范围内的非线性光束整形，同时也有助于更深入地理解多模非线性系统中光与物质相互作用的非凡物理特性。
Understanding and exploiting the dynamics of complex nonlinear systems is nowadays at the core of a broad range of scientific and technological endeavors. Within the optical domain, light evolution in a nonlinear multimode environment presents a formidable problem, as its chaotic evolution often hinders predictive insights. Recently, an optical thermodynamic framework has been put forward that, in a systematic manner, can not only predict but also harness the intricate behavior of these systems. In this work, by deploying entropic principles, we demonstrate a counterintuitive optical process in which light, launched into any input port of a judiciously designed nonlinear array, universally channels into a tightly localized ground state, a response that is completely unattainable in linear conservative arrangements. This phenomenon arises from the interplay between lattice structure and the way the kinetic and nonlinear Hamiltonian components unfold, leading to two optical thermal processes: a Joule-Thomson-like expansion followed by mode thermalization. Experimentally, this effect is demonstrated in properly configured nonlinear time-synthetic mesh lattices, where the optical temperature approaches near zero, causing light to condense at a single spot, regardless of the initial excitation position. The effect demonstrated here opens new avenues for applying the principles of optical thermodynamics in realizing novel optical functionalities, such as all-optical beam steering, multiplexing, and nonlinear beam shaping in high-power regimes, while also offering a greater understanding of the remarkable physics of light-matter interactions in multimode nonlinear systems.
交叉提交 (展示 5 之 5 条目 )
- [9] arXiv:2509.11341 (替换) [中文pdf, pdf, html, 其他]
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标题： 对流时空混沌作为确定性和随机湍流的动力学模型标题： Convective Space-Time Chaos as a Dynamical Model of Deterministic and Stochastic Turbulence主题： 混沌动力学 (nlin.CD)
最近，基于边界层的实验引入了确定性和随机湍流的概念。 在这些实验中，流动由受控的随机扰动驱动；此外，还存在自然环境噪声。 确定性特性表现为由于入口处相同随机扰动引起的湍流模式的可重复性（确定性湍流）。 来自自然噪声的非相同随机成分逐渐增长，并最终在下游主导流动（随机湍流）。 我们认为，这些特性可以通过探索对流时空混沌的概念来解释，在这种概念中，叠加在混沌状态上的次级扰动会增长，但在实验室参考系中移动远离。 我们通过两个简单的对流时空混沌模型来说明这一点，一个是描述流过平板的薄膜上波的偏微分方程，另一个是单向耦合的常微分方程组。 为了证明对流时空混沌，我们计算了对流Lyapunov指数的分布。 在不同相同实验运行中湍流场的可重复性对应于稳定动力系统对随机强迫的可靠性。 随机成分的出现通过空间Lyapunov指数进行量化。 我们展示了当驱动为准周期时，如何观察到场的有效随机化。 此外，我们讨论了时空对偶性，它将对流时空混沌中对边界条件的敏感性与标准混沌状态下对初始条件的敏感性联系起来。
Recently, a concept of deterministic and stochastic turbulence has been introduced based on experiments with a boundary layer. In these experiments, the flow was driven with controlled random perturbation; in addition, natural ambient noise was also present. Deterministic property manifested itself as repeatability of turbulence patterns induced by identical random perturbations at the inlet (deterministic turbulence). A stochastic non-identical component originating from natural noise grows and eventually dominates the flow further downstream (stochastic turbulence). We argue that these properties can be explained by exploring the concept of convective space-time chaos, where secondary perturbations on top of a chaotic state grow but move away in the laboratory reference frame. We illustrate this with two simple models of convective space-time chaos, one is a partial differential equation describing waves on a film flowing down a plate, and the other is a set of unidirectionally coupled ordinary differential equations. To prove convective space-time chaos, we calculate the profiles of the convective Lyapunov exponent. The repeatability of the turbulent field in different identical experimental runs corresponds to the reliability of stable dynamical systems in response to random forcing. The onset of the stochastic component is quantified with the spatial Lyapunov exponent. We demonstrate how an effective randomization of the field is observed when the driving is quasiperiodic. Furthermore, we discuss space-time duality, which links sensitivity to boundary conditions in the convective space-time chaos to the usual sensitivity to initial conditions in a standard chaotic regime.
- [10] arXiv:2511.14519 (替换) [中文pdf, pdf, html, 其他]
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标题： 二维散射的微扰非线性J矩阵方法标题： Perturbative nonlinear J-matrix method of scattering in two dimensions评论： 32页，6图，4表和28参考文献主题： 量子物理 (quant-ph) ; 精确可解与可积系统 (nlin.SI)
我们引入了一种微扰公式，用于二维散射的J矩阵方法的非线性扩展。 也就是说，我们在二维情况下获得了具有圆对称性的时间独立非线性薛定谔方程的散射矩阵。 该公式依赖于正交多项式乘积的线性化以及J矩阵方法工具的利用。 高斯求积积分近似在该方法的数值实现中起着关键作用。 我们提出了适用于一般ψ^{2n + 1}非线性的理论，其中n是一个自然数，并得到了三次和五次非线性，即ψ^3和ψ^5的结果。 在某些能量值处，我们观察到分岔现象，存在两个稳定解。 这种奇特而有趣的现象是底层非线性的明确标志和表现。
We introduce a perturbative formulation for a nonlinear extension of the J-matrix method of scattering in two dimensions. That is, we obtain the scattering matrix for the time-independent nonlinear Schrödinger equation in two dimensions with circular symmetry. The formulation relies on the linearization of products of orthogonal polynomials and on the utilization of the tools of the J-matrix method. Gauss quadrature integral approximation is instrumental in the numerical implementation of the approach. We present the theory for a general ψ^{2n + 1} nonlinearity, where n is a natural number, and obtain results for the cubic and quintic nonlinearities, ψ^3 and ψ^5. At certain value(s) of the energy, we observe the occurrence of bifurcation with two stable solutions. This curious and interesting phenomenon is a clear signature and manifestation of the underlying nonlinearity.
- [11] arXiv:2511.14708 (替换) [中文pdf, pdf, html, 其他]
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标题： 大动量有效理论中自归一化核子胶子PDF的系统研究标题： Systematic Study of the Self-Renormalized Nucleon Gluon PDF in Large-Momentum Effective Theory主题： 高能物理 - 格点 (hep-lat)
我们使用格点QCD中的自重整化大动量有效理论（LaMET）方法，对核子胶子部分子分布函数（PDF）进行了系统研究。 这项工作通过详细分析关键系统效应，包括规范链平滑、格点间距、介子质量以及核子提升动量，扩展了以前的胶子-PDF提取结果。 自重整化框架通过将格点矩阵元与微扰短距离信息结合，缓解了与威尔逊线自能和重整子贡献相关的紫外发散，从而保持正确的红外结构。 计算在由MILC合作组生成的$N_f=2+1+1$HISQ格点集合上进行，这些集合在三个格点间距和两个介子质量下生成，提升的核子态动量达到最高2.2 GeV。 我们从零动量矩阵元中确定重整化因子，并应用混合重整化来抑制离散化伪影。 在外推大分离行为并执行傅里叶变换后，我们重建准-PDF，并使用次领头阶威尔逊系数将其与光锥PDF匹配。 我们的结果表明，平滑和格点间距效应得到控制，相对于当前的$O(10^6)$统计数据，介子质量与格点间距的依赖性较弱；然而，动量依赖性仍然是一个重要的不确定性来源。 未来的工作，包括更大的提升动量，对于减少格点确定胶子PDF的系统误差以及推动LHC和未来电子-离子对撞机的精确QCD现象学至关重要。
We present a systematic study of the nucleon gluon parton distribution function (PDF) using the self-renormalized large-momentum effective theory (LaMET) approach in lattice QCD. This work extends previous gluon-PDF extractions by performing a detailed analysis of key systematic effects, including gauge-link smearing, lattice spacing, pion mass, and nucleon boost momentum. The self-renormalization framework mitigates ultraviolet divergences associated with Wilson-line self-energy and renormalon contributions by combining lattice matrix elements with perturbative short-distance information, thereby preserving the correct infrared structure. Calculations are performed on $N_f=2+1+1$ HISQ ensembles generated by the MILC Collaboration at three lattice spacings and two pion masses, with boosted nucleon states reaching momenta up to 2.2~GeV. We determine renormalization factors from zero-momentum matrix elements and apply hybrid renormalization to suppress discretization artifacts. After extrapolating large-separation behavior and performing Fourier transforms, we reconstruct quasi-PDFs and match them to lightcone PDFs using next-to-leading order Wilson coefficients. Our results demonstrate that smearing and lattice-spacing effects are under control, and pion-mass and lattice-spacing dependence is mild relative to the current $O(10^6)$ statistics; however, momentum dependence remains a significant source of uncertainty. Future work including even larger boost momenta will be essential to reduce systematics in lattice determinations of the gluon PDF and to advance toward precision QCD phenomenology at the LHC and the future Electron-Ion Collider.
- [12] arXiv:2503.08774 (替换) [中文pdf, pdf, html, 其他]
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标题： 混合关联函数的共形色散关系标题： Conformal dispersion relation for mixed correlators评论： 11页。第2版：更正了拼写错误；更新了讨论和参考文献。发表于《物理评论D快报》主题： 高能物理 - 理论 (hep-th)
色散关系是非微扰公式，将可观测量的紫外和红外行为联系起来，在线性响应理论、量子场论散射振幅和共形关联函数中有广泛的应用。 我们推导了任意共形场理论中标量四点混合关联函数的位置空间色散关系。 该公式将关联函数表示为其积分双不连续性乘以一个运动学核。 该核被解析计算，并以一种令人惊讶的简单形式表达为一个两变量的Appell函数。 通过求解核所满足的耦合偏微分方程，得到了色散核。 对广义自由场关联函数成功地进行了色散关系的数值检验。 最后，我们证明我们的位置空间色散关系等价于关联函数Mellin幅度的Cauchy型色散关系。
Dispersion relations are nonperturbative formulas that relate the ultraviolet and infrared behavior of an observable with wide-ranging applications applications in linear response theory, quantum field theory scattering amplitudes, and conformal correlators. We derive a position-space dispersion relation for scalar four-point mixed correlation functions in an arbitrary conformal field theory. This formula expresses the correlator in terms of its integrated double discontinuity times a kinematic kernel. The kernel is analytically computed, and expressed in a remarkably simple form as a two-variable Appell function. The dispersion kernel is found by solving a coupled partial differential equation that the kernel obeys. Numerical checks of the dispersion relation are successfully performed for generalized free field correlators. Finally, we show that our position-space dispersion relation is equivalent to a Cauchy-type dispersion relation of the Mellin amplitude of the correlator.
- [13] arXiv:2511.04629 (替换) [中文pdf, pdf, html, 其他]
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标题： 成对混合引起的时间反演破缺超导性标题： Pair-mixing induced Time-reversal-breaking superconductivity评论： 42页，7图主题： 超导性 (cond-mat.supr-con)
在过渡金属二硫化物（TMD）超导体4H$_b$-TaS$_2$或手性分子插层的TaS$_2$混合超晶格中，已经报道了超导基态自发时间反演（TR）对称性破缺的实验证据，并被视为新兴手性超导性的证据。 然而，这些TMD超导体的$T_c$与原始的1H或2H-TaS$_2$相当，后者没有表现出任何TR对称性破缺的迹象，并被认为是有常规Bardeen-Cooper-Schrieffer超导体。 为了解决这个谜题，我们提出了一种新的配对混合态，该态通过有限的库珀对动量将主导的常规s波配对通道与次主导的手性p波配对通道混合，这是基于Ginzburg-Landau理论中的对称性分析。 我们的分析表明，手性p波通道中的四阶项可以导致各种具有自发TR对称性破缺的配对混合态。 这些TR对称性破缺的超导态还揭示了一种零磁场、无结的超导二极管效应，这种效应在手性分子插层的TaS$_2$超晶格中被观察到。
Experimental evidences of spontaneous time-reversal (TR) symmetry breaking have been reported for the superconducting ground state in the transition metal dichalcogenide (TMD) superconductor 4H$_b$-TaS$_2$ or chiral molecule intercalated TaS$_2$ hybrid superlattices, and is regarded as evidence of emergent chiral superconductivity. However, the $T_c$ of these TMD superconductors is of the same order as pristine 1H or 2H-TaS$_2$, which do not show any signature of TR breaking and are believed to be conventional Bardeen-Cooper-Schrieffer superconductors. To resolve this puzzle, we propose a new type of pair-mixing state that mixes the dominant conventional s-wave pairing channel with the subdominant chiral p-wave pairing channel via a finite Cooper-pair momentum, based on symmetry analysis within the Ginzburg-Landau theory. Our analysis shows that the fourth-order terms in the chiral p-wave channel can lead to a variety of pair-mixing states with spontaneous TR breaking. These TR-breaking superconducting states also reveal a zero-field, junction-free superconducting diode effect that is observed in chiral molecule intercalated TaS$_2$ superlattices.
- [14] arXiv:2511.13737 (替换) [中文pdf, pdf, html, 其他]
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标题： 通过原点-命运图研究哈密顿系统的相空间动力学标题： Investigating the Phase Space Dynamics of Hamiltonian Systems by the Origin-Fate Map评论： 17页，22张图。在开普敦大学进行的关于拉伸穹顶势中相空间输运的独立研究项目，使用Origin-Fate Maps和Lagrangian Descriptors。补充动画可在https://doi.org/10.5281/zenodo.17062372获取。主题： 混沌动力学 (nlin.CD) ; 动力系统 (math.DS)
我们使用起源-命运图（OFM）框架结合拉格朗日描述符（LD）分析，研究二维拉伸火山势中的相空间传输。火山势是一个具有多个出口通道的反应动力学模型，通过拉伸因子lambda进行调整，该因子控制四鞍点景观的方向性偏差。使用前向和后向辛积分构建了两个庞加莱截面的多个OFMs，以将每个初始条件分配到一个起源通道和命运通道。我们的结果再现了Hillebrand等人在Phys. Rev. E 108, 024211, 2023中报告的高度对称lambda = 1.0模式，并揭示了较小lambda时明显的通道不平衡、双纽线传输环路和复杂的多通道混沌区域。长时间积分显示被俘获区域的边界在深度缩放下表现出自相似性，揭示了类似分形的结构。高分辨率OFMs和LD梯度图揭示了控制传输的叶瓣动力学和流形结构，显示出LD脊线与OFM边界之间的近乎完美的对齐。
We investigate phase space transport in a two-dimensional stretched caldera potential using the Origin-Fate Map (OFM) framework, complemented by Lagrangian Descriptor (LD) analysis. The caldera potential, a model for reaction dynamics with multiple exit channels, is adjusted by a stretching factor lambda that controls the directional bias of the four-saddle landscape. Several OFMs are constructed for two Poincare surfaces of section using forwards and backwards symplectic integration to assign each initial condition a channel of origin and fate. Our results reproduce the highly symmetric lambda = 1.0 patterns reported in Hillebrand et al. (Phys. Rev. E 108, 024211, 2023), and reveal, for smaller lambda, pronounced channel imbalance, figure-eight transport loops, and complex mixed-channel chaotic regions. Long-time integrations show a reduction of trapped regions with boundaries that exhibit self-similarity under deep zoom, revealing fractal-like structures. High-resolution OFMs and LD gradient maps uncover lobe dynamics and manifold structures that govern transport, showing near-perfect alignment between LD ridges and OFM boundaries.