PRL导读-2022年129卷11期
序 言
阅读导航
01 普通物理：统计与量子物理（4篇）
10 软物质与交叉科学（4篇）
01
普通物理：统计与量子物理
责编：艾清
01-01
闵可夫斯基时空中超光速信号的不可能性并不阻止因果循环的发生
因果律是科学的基础，它以几种不同的形式出现。第一个是相对论因果律，它与时空结构相关联，禁止在未来之外发信号。第二个是关于因果关系的操作型概念，它考虑的是物理体系之间的信息流以及对体系的干预。在[V. Vilasini and R. Colbeck, 循环和精调因果模型及其与时空兼容性的一般框架, Phys. Rev. A 106, 032204 (2022)]一文中，作者提出了一个框架来描述一个因果模型在什么情况下能够既不违背相对论的原则（比如说不能有超光速的信号）又允许循环和非经典因果影响，以及没有信号的因果关系的可能性。在没有超光速因果关系的理论中，超光速信号以及因果循环在闵可夫斯基时空中都是不可能的。在本文中，作者证明如果只禁止超光速信号那么超光速因果关系仍然可能存在，并给出了可以被嵌入到闵可夫斯基时空中而不引起超光速信号的因果循环的数学可能性。原则上，在给定时空中这种因果循环的存在可以通过干预来从操作方面验证。这表明禁止超光速信号的物理原则自身并不足以排除闵可夫斯基时空事件之间的因果循环。有趣的是，排除时空中因果循环所需要的条件与维度有关。这样的循环在三个空间维度中是否可能是一个重要的悬而未决的问题。
（赵秀花）
Impossibility of Superluminal Signaling in Minkowski Spacetime Does Not Rule Out Causal Loops
V. Vilasini and R. Colbeck
Phys. Rev. Lett. 129, 110401 (2022)
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.129.110401
01-02
量子Monge-Kantorovich问题和密度矩阵之间的传输距离
本文分析了Monge-Kantorovich最优传输问题的量子版本。在所有二分耦合状态ρAB的集合上，传输成本最小化，使得其 N 维的约化密度矩阵ρA和ρB都是固定的。作者表明，选择与反对称子空间上的投影成正比的量子成本矩阵，最小传输成本导致ρA和ρB之间的半距离，其下限为重新缩放的Bures 距离，下限为根不忠。在单量子比特情况下，作者提供了任意两个状态之间最优传输成本的半解析表达式，并证明了其平方根满足三角不等式，并在密度矩阵集上产生了一个类似于2阶Wasserstein距离。作者引入了一种关联的量子态接近度度量，称为交换保真度，并讨论了它的性质和在量子机器学习中的应用。
（刘承葛）
Quantum Monge-Kantorovich Problem and Transport Distance between Density Matrices
S. Friedland, M. Eckstein, et al.
Phys. Rev. Lett. 129, 110402 (2022)
01-03
耗散对量子开放系统中普适涨落动力学的影响
最近的研究从理论和实验上探索了与孤立量子系统中的表面生长物理相关的普适动力学。 在这项研究中，Fujimoto等人从理论上阐明了耗散极大地改变了与一维自由费米子和玻色子中的表面粗糙度增长相关的普适粒子数涨落动力学。 在导致空间相干性丧失的退相位系统中，作者通过数值计算发现表面粗糙度动力学的普适性类别从弹道类变为具有 Edwards-Wilkinson 标度指数和非常规标度函数的类。 作者通过重整化群技术从退相位 Lindblad 方程提供了扩散方程的解析推导，并成功地解释了这一剧烈变化。 此外，本文在数值上发现了在更加非平凡耗散下普适类的相同变化，即对称非相干跳跃。
(马宇翰)
Impact of Dissipation on Universal Fluctuation Dynamics in Open Quantum Systems
K. Fujimoto, R. Hamazaki, and Y. Kawaguchi
Phys. Rev. Lett. 129, 110403 (2022)
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.129.110403
01-04
单量子比特门的能量学
量子比特是物理的，因此量子门不仅会作用于量子比特携带的信息，还会作用于其能量。 那么量子比特和实现门的控制器之间的相应能流是什么？ 在本文中，Stevens等人在超导平台上回答这个问题，这里他们通过共振驱动场实现量子门。 在门操作中，超导量子比特与微波驱动脉冲纠缠在一起，因此能流之间存在量子叠加。 作者根据投影量子比特测量的结果测量驱动场中的能量变化。 他们证明，与测量反作用相关的驱动器能量变化可能远远超过量子比特可以提取的能量。 这可以通过将量子比特视为驱动场的弱测量装置来理解。
(马宇翰)
Energetics of a Single Qubit Gate
J. Stevens, D. Szombati, et al.
Phys. Rev. Lett. 129, 110601 (2022)
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.129.110601
02
引力与天体物理
导读：闫若帝；责编：郭敏勇
02-01
GW150914中的铃宕泛音分析
作者分析 GW150914 合并后数据，以了解铃宕泛音探测声明是否可靠。 该研究在波形到达峰值之后的数据中没有发现有利于泛音的证据。 在峰值附近，贝叶斯因子并不表示存在泛音，而支持非零振幅的数据对开始时间的变化敏感，远小于泛音阻尼时间。 这表明泛音检测的声明是噪声主导的。 作者还在真实检测器噪声的相邻段中执行类似 GW150914 的注入，并且结果表明噪声确实可以导致产生泛音的人工证据。
Analysis of Ringdown Overtones in GW150914
Roberto Cotesta, Gregorio Carullo and et al.
Phys. Rev. Lett. 129, 111102 (2022)
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.129.111102
02-02
在H.E.S.S.内银河系调查中搜索暗物质湮灭信号
The central region of the Milky Way is one of the foremost locations to look for dark matter (DM) signatures. We report the first results on a search for DM particle annihilation signals using new observations from an unprecedented γ-ray survey of the Galactic Center (GC) region, i.e., the Inner Galaxy Survey, at very high energies (≳100 GeV) performed with the H.E.S.S. array of five ground-based Cherenkov telescopes. No significant γ-ray excess is found in the search region of the 2014–2020 dataset and a profile likelihood ratio analysis is carried out to set exclusion limits on the annihilation cross section <σv>. Assuming Einasto and Navarro-Frenk-White (NFW) DM density profiles at the GC, these constraints are the strongest obtained so far in the TeV DM mass range. For the Einasto profile, the constraints reach <σv> values of 3.7 × 10−26 cm3 s−1 for 1.5 TeV DM mass in the W+W− annihilation channel, and 1.2 × 10−26 cm3 s−1 for 0.7 TeV DM mass in the τ+τ− annihilation channel. With the H.E.S.S. Inner Galaxy Survey, ground-based γ-ray observations thus probe <σv> values expected from thermal-relic annihilating TeV DM particles.
Search for Dark Matter Annihilation Signals in the H.E.S.S. Inner Galaxy Survey
H. Abdalla, F. Aharonian and et al.
Phys. Rev. Lett. 129, 111101 (2022)
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.129.111101
02-03
普朗克卫星对银河系极化同步激发的观测对暗物质的约束
银河系中的暗物质 (DM) 湮灭可能会产生线性极化的同步加速器信号。通过将理论预测与普朗克卫星合作获得的最新极化图进行比较，作者首次使用同步加速器极化来约束 DM 湮没截面。该研究发现同步加速器极化通常比同步加速器受约束更大，强度约1个数量级，这与电子和正电子传播，或银河系磁场建模中的不确定性无关。 对于亲轻子DM的情况，该研究的界限与宇宙微波背景相互限制。
Dark Matter Constraints from Planck Observations of the Galactic Polarized Synchrotron Emission
Silvia Manconi, Alessandro Cuoco and et al.
Phys. Rev. Lett. 129, 111103 (2022)
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.129.111103
02-04
用宇宙对撞机探测轻子物质的产生
由于涉及的能量尺度非常高，因此直接测试轻子物质产生的过程通常具有挑战性。 在该研究中，作者提出了一种利用宇宙对撞机的物理机制进行轻子生成的新探测方法。以宇宙学希格斯对撞机为例，作者证明了在暴胀期间，轻子生成模型可以产生可检测的原始非高斯性信息，其具有独特的振荡模式，包含了有关轻子数违反耦合、马约拉纳右手中微子质量和CP相的信息，这些对轻子形成至关重要。
Probing Leptogenesis with the Cosmological Collider
Yanou Cui and Zhong-Zhi Xianyu
Phys. Rev. Lett. 129, 111301 (2022)
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.129.111301
02-05
量子和量子经典系统中的动力学和纠缠：引力的借鉴
Motivated by quantum gravity, semiclassical theory, and quantum theory on curved spacetimes, we study the system of an oscillator coupled to two spin-1=2 particles. This model provides a prototype for comparing three types of dynamics: the full quantum theory, the classical oscillator with spin backreaction, and spins propagating on a fixed oscillator background. From calculations of oscillator and entanglement entropy evolution, we find the three systems give equivalent dynamics for sufficiently weak oscillator-spin couplings but deviate significantly for intermediate couplings. These results suggest that semiclassical dynamics with backreaction does not provide a suitable intermediate regime between quantum gravity and quantum theory on curved spacetime.
Dynamics and Entanglement in Quantum and Quantum-Classical Systems: Lessons for Gravity
Viqar Husain, Irfan Javed and et al.
Phys. Rev. Lett. 129, 111302 (2022)
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.129.111302
02-06
小加速度下安鲁效应的空腔优化
One of the primary reasons behind the difficulty in observing the Unruh effect is that for achievable acceleration scales the finite temperature effects are significant only for the low frequency modes of the field. Since the density of field modes falls for small frequencies in free space, the field modes which are relevant for the thermal effects would be less in number to make an observably significant effect. In this Letter, we investigate the response of an Unruh-DeWitt detector coupled to a massless scalar field which is confined in a long cylindrical cavity. The density of field modes inside such a cavity shows a resonance structure, i.e., it rises abruptly for some specific cavity configurations. We show that an accelerating detector inside the cavity exhibits a nontrivial excitation and de-excitation rates for small accelerations around such resonance points. If the cavity parameters are adjusted to lie in a neighborhood of such resonance points, the (small) acceleration-induced emission rate can be made much larger than the already observable inertial emission rate. We comment on the possibilities of employing this detector-field-cavity system in the experimental realization of the Unruh effect, and argue that the necessity of extremely high acceleration can be traded off in favor of precision in cavity manufacturing for realizing noninertial field theoretic effects in laboratory settings.
Cavity Optimization for Unruh Effect at Small Accelerations
D. Jaffino Stargen and Kinjalk Lochan
Phys. Rev. Lett. 129, 111303 (2022)
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.129.111303
03
基本粒子与场论
责编：晁伟，刘晓辉
03-01
用CUPID-0探测82 Se无中微子双贝塔衰变的最终结果
CUPID-0， 回旋量能器阵列是第一个中等规模闪烁辐射热测量仪技术的验证。首个阶段（2017年3月-2018年12月）的实验对 同位旋的无中微子双贝塔衰变的半衰期进行了最严格的限制。在6个月的探测器升级后，CUPID-0开始了它的第二个也是最后一个阶段（2019年6月-2020年2月）。在本文中，作者描述了用8.82kg yr-1的完全曝光量（1期+2期）搜索 无中微子双贝塔衰变的结果。作者给出了 到基态 的半衰期为 年（90%置信度），对应于有效Majorana中微子质量 。作者还给出了最严格的 到 , , 和 激发态的无中微子衰变半衰期下限，分别为1.8×1023 年, 3.0×1023 年, 以及3.2×1023 年(90%置信度)。
Final Result on the Neutrinoless Double Beta Decay of 82 Se with CUPID-0
O. Azzolini et al.
Phys. Rev. Lett. 129, 111801 (2022)
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.129.111801
03-02
利用19.6 μ eV的晕望远镜的台湾轴子搜索实验的首个结果
This Letter reports on the first results from the Taiwan Axion Search Experiment with a Haloscope, a search for axions using a microwave cavity at frequencies between 4.707 50 and 4.798 15 GHz. Apart from the nonaxion signals, no candidates with a significance of more than 3.355 were found. The experiment excludes models with the axion-two-photon coupling |gaγγ|≳8.1×10−14 GeV−1, a factor of eleven above the benchmark Kim-Shifman-Vainshtein-Zakharov model, in the mass range 19.4687<ma<19.8436 μeV. It is also the first time that a haloscope experiment places constraints on gaγγ in the mass region of 19.4687<ma<19.7639 μeV, reaching a sensitivity 3 orders of magnitude better than the limits obtained by nonhaloscope experiments.
First Results from the Taiwan Axion Search Experiment with a Haloscope at 19.6 μeV
Hsin Chang et al. (TASEH Collaboration)
Phys. Rev. Lett. 129, 111802 (2022)
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.129.111802
03-03
平面角关联作为顶夸克喷注的一种亚结构
作者提出一种新颖的加速顶夸克的喷注亚结构观测量，该观测量与顶夸克衰变产生的W玻色子线性极化相关联，会在 和 衰变平面产生cos2ϕ的角关联。作者用Wigner小群变换自习讨论了该线性极化的来源。作者论证cos2ϕ只存在于顶夸克被加速的区域，而不存在于其静止系。作者利用在顶夸克喷注内的横向能量沉积不对称为该关联构建了不需要重建W衰变产物的实验可观测量。这样的不对称度可以用来测量顶夸克的纵向极化，这将是探索耦合到顶夸克的新物理的重要渠道，并可以用来从诸如QCD喷注的背景中区分加速顶夸克。作者给出了数值模拟并发现与标准模型的解析预言吻合。
Azimuthal Angular Correlation as a Boosted Top Jet Substructure
Zhite Yu and C.-P. Yuan
Phys. Rev. Lett. 129, 112001 (2022)
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.129.112001
03-04
用带电介子衰变的新物理解释MiniBooNE反常
We point out that production of new bosons by charged meson decays can greatly enhance the sensitivity of beam-focused accelerator-based experiments to new physics signals. This enhancement arises since the charged mesons are focused and their three-body decays do not suffer from helicity suppression in the same way as their usual two-body decays. As a realistic application, we attempt to explain the MiniBooNE low energy excess utilizing this overlooked mechanism, uniquely realizing dark-sector interpretations as plausible solutions to the excess. As proof of the principle, we consider two well-motivated classes of dark-sector models, models of vector-portal dark matter and models of long-lived (pseudo)scalar. We argue that the model parameter values to accommodate the excess are consistent with existing limits and that they can be tested at current and future accelerator-based neutrino experiments.
Solutions to the MiniBooNE Anomaly from New Physics in Charged Meson Decays
Bhaskar Dutta, et al.
Phys. Rev. Lett. 129, 111803 (2022)
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.129.111803
03-05
Υ衰变道双璨偶素的高阶QCD修正
作者研究了Υ到J/ψ与ηc (χc0,1,2)衰变。在NRQCD框架下，作者将不同螺旋度结构的衰变宽度计算到了QCD的次领头阶。作者发现QCD的修正显著地减弱了各个过程衰变宽度对重整化标度的依赖。ϒ→J/ψ+χc1的衰变分支比为 与Belle的测量Br(ϒ→J/ψ+χc1)=(3.90±1.21±0.23)×10−6一致。对于其它过程，除了外ϒ(2S)→ϒ→J/ψ+χc1,作者的结果与Belle实验给出的上限相吻合。有了极化宽度后，作者研究了J/ψ极化，并发现与非微扰参数无关。进一步地，根据作者的计算，作者发现由于其高亮度，超级B工厂可以测量所有涉及的过程。
Higher-Order QCD Corrections to Υ Decay into Double Charmonia
Yu-Dong Zhang, Wen-Long Sang, and Hong-Fei Zhang
Phys. Rev. Lett. 129, 112002 (2022)
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.129.112002
03-06
在 和 的 反冲质量谱中发现中性近阈结构的证据
We study the processes and , as well as their charge conjugated processes, at five center-of-mass energies between 4.628 and 4.699 GeV, using data samples corresponding to an integrated luminosity of 3.8 fb−1 collected by the BESIII detector at the BEPCII storage ring. Based on a partial reconstruction technique, we find evidence of a structure near the thresholds for Ds+D*− and Ds*+D− production in the KS0recoil-mass spectrum, which we refer to as the Zcs0(3985). Fitting with a Breit-Wigner line shape, we find the mass of the structure to be (3992.2±1.7±1.6) MeV/c2 and the width to be ( ) MeV, where the first uncertainties are statistical and the second are systematic. The significance of the Zcs0 (3985) signal is found to be 4.6σ including both the statistical and systematic uncertainty. We report the Born cross section multiplied by the branching fraction at different energy points. The mass of the Zcs0 (3985) is close to that of the Zcs(3985)+. Assuming SU(3) symmetry, the cross section of the neutral channel is consistent with that of the charged one. Hence, we conclude that the Zcs0 (3985) is the isospin partner of the Zcs(3985)+.
Evidence for a Neutral Near-Threshold Structure in the Recoil-Mass Spectra in and
M. Ablikim et al. (BESIII Collaboration)
Phys. Rev. Lett. 129, 112003 (2022)
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.129.112003
04
原子核物理
导读：王亚坤；责编：耿立升
04-01
N = 50同中子素中πg9/2壳部分辛弱数守恒的证据
R. M. Pérez-Vidal等人利用多核子转移反应实验，测量了原子核92Mo和94Ru中 和 的约化跃迁概率，以及原子核90Zr中 和 的约化跃迁概率。基于价质子空间为f5/2, p3/2, p1/2和g9/2的现实壳模型计算，他们解释了相应的实验结果。只有将大量的寿命信息和大规模的壳模型计算相结合，才能够理解在N = 50 g9/2 轨道中辛弱数是否守恒。他们的研究结果表明在第一个质子g9/2 轨道中辛弱数很大程度上是守恒的。
Evidence of Partial Seniority Conservation in the πg9/2 Shell for the N = 50 Isotones
R. M. Pérez-Vidal et al.
Phys. Rev. Lett. 129, 112501 (2022)
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.129.112501
05
原子、分子与光学
导读：冉光柳；责编：张文凯
05-01
连续对称性自发破缺的可伸缩自旋压缩
自发对称破缺是哈密顿平衡态的一种性质，在热力学极限下，即使在与之耦合的场绝热关闭后，该平衡态仍保持序参数的有限平均值。在具有连续对称的量子自旋模型中，作者证明了这一绝热过程还伴随着对称发生器即沿着对称轴的集体自旋分量波动的抑制。在S = 1 / 2自旋或量子比特的系统中，单向波动的抑制和横向磁化的持续共同作用导致了自旋压缩，这是量子态中一个非常受欢迎的特性，既用于纠缠检测，也可用于计量。关注XXZ模型自发破缺U(1)[甚至SU(2)]对称性的情况，作者证明了绝热制备态具有几乎最小的自旋不确定性;利用这些状态所能实现的最小相位不确定性与自旋数N成比例关系为N-3/4;该比例是绝热制备时间随N线性缩放后得到的。作者的发现打开了在包括光晶格时钟在内的多种量子多体装置中强自旋压缩态的绝热制备的大门。
Scalable Spin Squeezing from Spontaneous Breaking of a Continuous Symmetry
Tommaso Comparin, et al.
Phys. Rev. Lett. 129, 113201 (2022)
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.129.113201
05-02
亚反冲时钟跃迁激光冷却使浅光晶格钟成为可能
激光冷却是在各种环境中对原子系统进行量子控制的关键因素。在二价原子中，两级多普勒冷却通常用于使原子达到μK范围。在这里，作者使用镱中的超窄1S0-3P0时钟跃迁实现脉冲径向冷却方案，以实现低至数十nK的亚反冲温度。结合沿一维晶格轴的边带冷却，作者以6个晶格反冲的能量有效地制备了浅晶格中的原子。在这些条件下，晶格时钟精度和不稳定性的关键限制降低了，为大幅度改进打开了大门。此外，在浅晶格中隧穿位移不会影响10-19量级的时钟精度。
Subrecoil Clock-Transition Laser Cooling Enabling Shallow Optical Lattice Clocks
X. Zhang, K. et al.
Phys. Rev. Lett. 129, 113202 (2022)
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.129.113202
05-03
非厄米准晶体中的拓扑相变和迁移率边
非厄米性极大地丰富了拓扑模型的特性，导致了非厄米趋肤效应和非布洛赫体边界对应等奇异特征，而这些特征在厄米设置中是没有对应的。它的影响在非厄米准晶体中表现得尤为明显，非厄米和准周期性之间的相互作用导致离域-定域跃迁、时空(PT)-对称性破缺和非厄米趋肤效应的发生。在这里，作者用光子量子行走实验模拟了非厄米准晶体。利用动态可观测值，作者证明了系统可以从一个具有非厄米趋肤效应的离域PT对称破缺相过渡到一个不具有非厄米趋肤效应的定域PT对称非破缺相。测得的临界点通过光谱绕组的理论预测一致，证实了相变的拓扑起源。更有趣的是，作者还首次提供了由非厄米性引起的迁移率边的实验证据。作者的工作为研究开放量子系统中非厄米性、准周期性和光谱拓扑的相互作用开辟了道路。
Topological Phase Transitions and Mobility Edges in Non-Hermitian Quasicrystals
Quan Lin, et al.
Phys. Rev. Lett. 129, 113601 (2022)
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.129.113601
06
非线性动力学和流体力学
导读：曹环宇；责编：兰岳恒
06-01
多普勒陀螺仪：频率与相位估计
Howell等人考虑频率与相位在参数估计中 (特别是在Sagnac效应中)的基本作用。文章基于液晶光阀的极陡频率相关增益描述了一种新型的超灵敏陀螺仪。作者提供了令人信服的实验证据，证明多普勒频移是萨格纳克效应的基础，从而澄清了一个长期争论的问题。本文的实验表明，相对于基于相位估计的陀螺仪标准量子极限，其灵敏度提高了几个数量级。
Doppler Gyroscopes: Frequency vs Phase Estimation
John C. Howell, et al.
Phys. Rev. Lett. 129, 113901 (2022)
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.129.113901
06-02
Fermi-Pasta-Ulam-Tsingou链中的Burgers湍流
We prove analytically and show numerically that the dynamics of the Fermi-Pasta-Ulam-Tsingou chain is characterized by a transient Burgers turbulence regime on a wide range of time and energy scales. This regime is present at long wavelengths and energy per particle small enough that equipartition is not reached on a fast timescale. In this range, we prove that the driving mechanism to thermalization is the formation of a shock that can be predicted using a pair of generalized Burgers equations. We perform a perturbative calculation at small energy per particle, proving that the energy spectrum of the chain Ek decays as a power law, Ek ∼ k−ζ(t), on an extensive range of wave numbers k. We predict that ζ(t) takes first the value 8=3 at the Burgers shock time, and then reaches a value close to 2 within two shock times. The value of the exponent ζ = 2 persists for several shock times before the system eventually relaxes to equipartition. During this wide time window, an exponential cutoff in the spectrum is observed at large k, in agreement with previous results. Such a scenario turns out to be universal, i.e., independent of the parameters characterizing the system and of the initial condition, once time is measured in units of the shock time.
Burgers Turbulence in the Fermi-Pasta-Ulam-Tsingou Chain
Matteo Gallone, et al.
Phys. Rev. Lett. 129, 114101 (2022)
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.129.114101
07
等离子体与束物理
责编：陈少永，牟茂淋
07-01
超薄氘化箔中的稳定辐射压力加速和中子产生
超薄激光辐照靶的相对论性过早透明是实现“光帆”(LS)模式下稳定辐射压力加速的障碍。实验数据与二维PIC模拟结果相印证，表明高Z材料表面几纳米厚的覆盖层在加速过程中显著改善了高能离子的聚集。这是通过在氘化塑料靶辐照后同时进行离子和中子光谱诊断得到的。特别地，在最佳参数下，作为加速过程中等离子体层完整性的标志，大量定向中子产生(显著大于其他靶内方案)。
（刘泰齐）
Stabilized Radiation Pressure Acceleration and Neutron Generation in Ultrathin Deuterated Foils
A. Alejo, et al.
Phys. Rev. Lett. 129, 114801 (2022)
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.129.114801
07-02
轴对称标准磁旋不稳定性的实验室观测
Yin Wang等人报告了轴对称标准磁旋转不稳定性(SMRI)的第一个直接证据，该证据来自对具有独立旋转和导电端盖的Taylor-Couette电池中磁化液态-金属剪切流的实验和数值研究。当沿旋转轴施加均匀的垂直磁场Bi时，由于残余Ekman循环的磁化作用，内筒上测得的径向磁场Br随磁雷诺数Rm的减小而线性增大。在实验和非线性数值模拟中，轴对称SMRI的出现是由Br的非线性增加超过临界Rm决定的。轴对称SMRI仅存在于足够大Rm和中等大小Bi的条件下，这一特征与理论预测一致。模拟进一步表明，轴对称SMRI导致速度和磁场在主体区域贡献轴向角动量的向外通量，就像在吸积盘中一样。
（刘泰齐）
Observation of Axisymmetric Standard Magnetorotational Instability in the Laboratory
Yin Wang, et al.
Phys. Rev. Lett. 129, 115001 (2022)
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.129.115001
07-03
激光等离子体中回流不稳定性的直接测量
Milder等人对回流不稳定性增长率进行了测量，结果表明它与非局域输运同时存在。汤姆森散射测得最大增长率为5.1×109 Hz，比经典的Spitzer-Härm理论预测值小3倍。测得的等离子体条件表明热通量是非局域的，并且非局域Vlasov-Fokker-Planck模拟再现了测得的增长率。此外，测得的回流不稳定性阈值（ ）与先前的理论模型非常吻合。
（李勇健）
Direct Measurement of the Return Current Instability in a Laser-Produced Plasma
A. L. Milder, et al.
Phys. Rev. Lett. 129, 115002 (2022)
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.129.115002
07-04
单分散复合等离子体中方形晶格的形成
Swarnima Singh等人首次观察到单分散复合等离子体系统中方形晶格的形成，这是一种构型转变现象，长期以来一直是该领域的实验挑战。实验在桌面L形尘埃等离子体实验装置上，直流辉光放电氩等离子体环境中进行。通过仔细控制约束带电粒子的垂直电位以及离子尾场电荷与尘埃粒子相互作用的强度，能够将系统引导向呈现方形晶格的结晶相。转变发生于垂直约束强度降低至略微低于临界值时，这导致了单分散六方二维尘埃晶体屈曲，并形成窄的分离双层状态（准二维状态）。实验相关参数的分子动力学模拟结果，提供了对转变过程的一些理论见解。
（李勇健）
Square Lattice Formation in a Monodisperse Complex Plasma
Swarnima Singh, et al.
Phys. Rev. Lett. 129, 115003 (2022)
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.129.115003
09
凝聚态物理：电子性质
责编：袁喆，马锋杰
09-01
超导体上分子的共振增强振动光谱
[编辑推荐] 使用超导材料可以将扫描隧道光谱信号的强度提高多达50倍，从而可以检测到单个分子振动能量的微小变化。
使用扫描隧道显微镜探测分子振动光谱是可行的，但通常只能探测到很少的振动模式。Homberg等人利用超导体上的分子观察到尖锐的Yu-Shiba-Rusinov 态来显著地增强振动信号。他们从铅酞菁分子中分辨出46个振动峰，从而能够与计算的模式进行比较。能量分辨率提高到超过了热展宽的极限，并确定了由相邻分子引起的位移或显微镜尖端的位置。反之亦然，利用振动模式的光谱也可以测量电场对Yu-Shiba-Rusinov态能量的影响。这个方法有助于进一步探索分子与环境的相互作用，更好地理解振动激发的选择规律。
(赵鑫磊)
Resonance-Enhanced Vibrational Spectroscopy of Molecules on a Superconductor
Jan Homberg et al.
Phys. Rev. Lett. 129, 116801 (2022)
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.129.116801
09-02
手性晶体中的旋转、电场响应和绝对对映体选择
The microscopic origin of chirality, possible electric-field induced static rotational lattice deformation, and rotation-field induced electric polarization are investigated. By building up a realistic tight-binding model for the elemental Te crystal in terms of a symmetry-adapted basis, we identify the microscopic origin of the chirality and essential couplings among polar and axial vectors with the same time-reversal properties. Based on this microscopic model, we elucidate quantitatively that an interband process, driven by nearest-neighbor spin-dependent imaginary hopping, is the key factor in the electric-field induced rotation and its inverse response. From the symmetry point of view, these couplings and responses are characteristic and common to any chiral material, leading to a possible experimental approach to achieve absolute enantioselection by simultaneously applied electric and rotation fields, or a magnetic field and electric current, and so on, as a conjugate field of the chirality.
Rotation, Electric-Field Responses, and Absolute Enantioselection in Chiral Crystals
Rikuto Oiwa and Hiroaki Kusunose
Phys. Rev. Lett. 129, 116401 (2022)
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.129.116401
09-03
外延石墨烯中转角铅烯近邻诱导的能隙打开
[编辑推荐] 插层稳定的铅烯是一种铅基石墨烯类似物，在低温下会出现能隙，从而导致金属-绝缘体转变。
除了石墨烯之外，在不同的表面上还成功地合成了更多的蜂窝状二维结构。然而，几乎平的铅烯拥有的拓扑保护的边缘态尚未实现。在本文中，Ghosal等研究了Pb在SiC (0001)表面缓冲层上的插入。因此，出现了悬浮和电荷中性的石墨烯，且插入的铅形成了铅蜂窝晶格，相对于石墨烯旋转了 ± 7.5 °。伴随着这种扭转，近邻诱导的石墨烯中跃迁系数的调制在费米能级处打开了大约30meV的带隙，引起了金属-绝缘体转变。此外，铅烯插层的边缘在大约 1 eV 的导带间隙内显现出边缘态，正如对电荷中性铅烯所预期的那样。
(赵鑫磊)
Proximity-Induced Gap Opening by Twisted Plumbene in Epitaxial Graphene
Chitran Ghosal et al.
Phys. Rev. Lett. 129, 116802 (2022)
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.129.116802
09-04
石墨烯中整数和分数量子霍尔边缘模式的热平衡
[编辑推荐]中性模式，即无电荷的手性传输通道，携带能量沿着样品的边缘朝与电流相反的方向移动，可以耦合到所有带电通道。
分数量子霍尔效应的空穴共轭态反向传播的边缘通道被认为能够交换电荷与能量，这些交换是理论与实验研究的主题，尤其是还不清楚由完全填充的朗道能级产生的整数量子霍尔边缘通道的存在是否会影响边缘的热平衡。在本文中，作者介绍了石墨烯量子霍尔态中热传输的测量，证明了整数通道可以与分数通道强烈的平衡，这导致依赖于边缘静电的量子化热传输机制变得明显不同。作者的结果能够更好的理解分数量子霍尔机制中复杂的边缘物理。
（郭儒达）
Heat Equilibration of Integer and Fractional Quantum Hall Edge Modes in Graphene
G. Le Breton et al.
Phys. Rev. Lett. 129, 116803 (2022)
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.129.116803
09-05
莫尔朗道扇和魔术零点
[编辑推荐] 确定了莫尔超晶格和磁场中一般色散电子实现完全平坦陈能带的普适条件。
Paul等人研究了均匀磁场作用下莫尔系统的能谱。超晶格势通常将朗道能级扩展到带宽有限的Chern能带。然而，他们发现这些陈能带在离散的磁场中变得平坦，并称之为“魔术零点”。在没有莫尔超晶格的情况下，平带子空间通常与朗道能级子空间不同。通过发展一种半经典量子化方法，并考虑超晶格诱导的布拉格反射，他们证明了魔术零点来自两个不同的 k 空间轨道的同时量子化。例如，他们展示了在特殊场下，对于任意的扭转角，TBG 的手征模在|n|>1的第n个朗道能级中都有平坦的带。奇异零点处的平带为探索晶体分数量子霍尔物理提供了一个新的环境。
(赵鑫磊)
Moiré Landau Fans and Magic Zeros
Nisarga Paul et al.
Phys. Rev. Lett. 129, 116804 (2022)
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.129.116804
09-06
Si和Ge量子点中空穴自旋量子比特的反常零场分裂
An anomalous energy splitting of spin triplet states at zero magnetic field has recently been measured in germanium quantum dots. This zero-field splitting could crucially alter the coupling between tunnel-coupled quantum dots, the basic building blocks of state-of-the-art spin-based quantum processors, with profound implications for semiconducting quantum computers. We develop an analytical model linking the zero-field splitting to the Rashba spin-orbit interaction that is cubic in momentum. Such interactions naturally emerge in hole nanostructures, where they can also be tuned by external electric fields, and we find them to be particularly large in silicon and germanium, resulting in a significant zero-field splitting in the μ eV range. We confirm our analytical theory by numerical simulations of different quantum dots, also including other possible sources of zero-field splitting. Our findings are applicable to a broad range of current architectures encoding spin qubits and provide a deeper understanding of these materials, paving the way toward the next generation of semiconducting quantum processors.
Anomalous Zero-Field Splitting for Hole Spin Qubits in Si and Ge Quantum Dots
B. Hetényi et al.
Phys. Rev. Lett. 129, 116805 (2022)
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.129.116805
09-07
近邻超导体对磁振子的有效门控
静电门控限制和控制集成电路中的电子输运。磁振子是磁序自旋波的量子，是很有前途的替代信息载体，但很难门控。在本文中，作者报道了薄磁性薄膜上的超导条带对磁振子杂散场的抗磁响应可以完全反射磁振子。诱导的大频移单向地阻止磁振子沿垂直磁化的方向传播。两个与磁化平行的超导门形成一个磁腔。门控相干磁振子的选项增加了磁振子器件的功能，例如可重新编程逻辑器件和增加其与其它自由度的耦合。
（刘芮西）
Efficient Gating of Magnons by Proximity Superconductors
T. Yu and G. Bauer
Phys. Rev. Lett. 129, 117201 (2022)
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.129.117201
09-08
非共线反铁磁体中矢量自旋塞贝克效应的观测
Spintronic phenomena to date have been established in magnets with collinear moments, where the spin injection through the spin Seebeck effect (SSE) is always along the out-of-plane direction. Here, we report the observation of a vector SSE in a noncollinear antiferromagnet (AF) LuFeO3, where temperature gradient along the out-of-plane and also the in-plane directions can both inject a pure spin current and generate a voltage in the heavy metal via the inverse spin Hall effect (ISHE). We show that the thermovoltages are due to the magnetization from canted spins in LuFeO3. Furthermore, in contrast to the challenges of generating, manipulating, and detecting spin current in collinear AFs, the vector SSE in LuFeO3 is readily viable in zero magnetic field and can be controlled by a small magnetic field of about 150 Oe at room temperature. The noncollinear AFs expand new realms for exploring spin phenomena and provide a new route to low-field antiferromagnetic spin caloritronics and magnonics.
Observation of Vector Spin Seebeck Effect in a Noncollinear Antiferromagnet
J. Xu et al.
Phys. Rev. Lett. 129, 117202 (2022)
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.129.117202
09-09
亚稳态铁电体挠曲电驱动的极化的机械转换
Flexoelectricity-based mechanical switching of ferroelectric polarization has recently emerged as a fascinating alternative to conventional polarization switching using electric fields. Here, we demonstrate hyperefficient mechanical switching of polarization exploiting metastable ferroelectricity that inherently holds a unique mechanical response. We theoretically predict that mechanical forces markedly reduce the coercivity of metastable ferroelectricity, thus greatly bolstering flexoelectricity-driven mechanical polarization switching. As predicted, we experimentally confirm the mechanical polarization switching via an unusually low mechanical force (100 nN) in metastable ferroelectric CaTiO3. Furthermore, the use of low mechanical forces narrows the width of mechanically writable nanodomains to sub-10 nm, suggesting an ultrahigh data storage density of ≥ 1 Tbit cm−2. This Letter sheds light on the mechanical switching of ferroelectric polarization as a viable key element for next-generation efficient nanoelectronics and nanoelectromechanics.
Flexoelectricity-Driven Mechanical Switching of Polarization in Metastable Ferroelectrics
Ji Hye Lee et al.
Phys. Rev. Lett. 129, 117601 (2022)
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.129.117601
09-10
转角双层石墨烯关联绝缘体的光谱
We analytically compute the scanning tunneling microscopy (STM) signatures of integer-filled correlated ground states of the magic angle twisted bilayer graphene (TBG) narrow bands. After experimentally validating the strong-coupling approach at ±4 electrons/moiré unit cell, we consider the spatial features of the STM signal for 14 different many-body correlated states and assess the possibility of Kekulé distortion (KD) emerging at the graphene lattice scale. Remarkably, we find that coupling the two opposite graphene valleys in the intervalley-coherent (IVC) TBG insulators does not always result in KD. As an example, we show that the Kramers IVC state and its nonchiral U(4) rotations do not exhibit any KD, while the time-reversal-symmetric IVC state does. Our results, obtained over a large range of energies and model parameters, show that the STM signal and Chern number of a state can be used to uniquely determine the nature of the TBG ground state.
Spectroscopy of Twisted Bilayer Graphene Correlated Insulators
Dumitru Călugăru et al.
Phys. Rev. Lett. 129, 117602 (2022)
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.129.117602
09-11
钙钛矿中自旋诱导铁电和铁磁性的共存与耦合
自旋感应铁电通常不会发生在具有简单共线磁性结构的钙钛矿中。在本文中，作者证明了在偶数层钙钛矿系统中，一些常见的畸变模式如八面体旋转和Jahn-Teller畸变，可以破坏反演对称性，从而在简单的磁性结构中出现与自旋相关的面外极化。这种自旋诱导的铁电性在双钙钛矿系统中非常常见，并且可以与室温以上的铁磁性或亚铁磁性共存。作者通过修改自旋相关的p-d杂化机制来解释它的起源。作者的研究为二维多铁性材料提供了通用的设计方案，并能够通过磁场控制极化。
（郭儒达）
Coexistence and Coupling of Spin-Induced Ferroelectricity and Ferromagnetism in Perovskites
J. Zhang et al.
Phys. Rev. Lett. 129, 117603 (2022)
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.129.117603
09-12
具有毫秒相干寿命的近表面125Te+自旋
Impurity spins in crystal matrices are promising components in quantum technologies, particularly if they can maintain their spin properties when close to surfaces and material interfaces. Here, we investigate an attractive candidate for microwave-domain applications, the spins of group-VI 125Te+ donors implanted into natural Si at depths as shallow as 20 nm. We show that surface band bending can be used to ionize such near-surface Te to spin-active Te+ state, and that optical illumination can be used further to control the Te donor charge state. We examine spin activation yield, spin linewidth, and relaxation (T1) and coherence times (T2) and show how a zero-field 3.5 GHz “clock transition” extends spin coherence times to over 1 ms, which is about an order of magnitude longer than other near-surface spin systems.
Near-Surface 125Te+ Spins with Millisecond Coherence Lifetime
M. Šimėnas et al.
Phys. Rev. Lett. 129, 117701 (2022)
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.129.117701
10
软物质与交叉科学
导读：张鑫洁；责编：严钢
10-01
脉冲序列波形驱动的受挫手性向列相中的旋转-时间对称性破缺
[编辑推荐]液晶可以支持行波，显示出控制分子取向的新能力。
本文报道了液晶取向运动中波形诱导的旋转-时间对称性破缺现象。填充了负介电各向异性手性向列相的垂面排列细胞表现出持续且可见的指向矢取向波，其时间周期至少为30个驱动场周期。它们在驱动波形参数空间中的存在性，以及利用这种同时表现出空间和时间长程有序的系统作为离散时间晶体实验研究的建模工具的可能性也进行了探讨。
Rotation-Time Symmetry Breaking in Frustrated Chiral Nematic Driven by a Pulse-Train Waveform
Vitaly P. Panov et al.
Phys. Rev. Lett. 129, 117801 (2022)
10-02
曲面上的主动向列相流
[编辑推荐]根据一项新的理论，当上皮组织细胞在曲面上移动时，它们会表现出不同于在平面上形成的模式。
细胞单分子层是组织生物物理学研究的核心模型系统。在体内，上皮组织在微米尺度上弯曲，而这种弯曲在自发组织流动发生中的作用仍知之甚少。Bell等人提出了一个在弯曲流形中存在上下不对称的主动向列相流体力学框架。研究表明，与平面空间相比，表面曲率在本质上改变了单层运动：由此产生的流动可以是无阈值的，并且运动的相变可从连续变为不连续。表面曲率、摩擦力和主动牵引力都被证实可以控制所选择的流动模式，从简单的剪切到涡旋链。
Active Nematic Flows over Curved Surfaces
Samuel Bell et al.
Phys. Rev. Lett. 129, 118001 (2022)
10-03
相互作用系统中局部时间箭头的分解
[编辑推荐]研究人员开发了一种定量评估复杂网络中不可逆性的方法。
本文作者证明了局部时间箭头的证据相当于热力学系统中的熵产生，是可以被分解的。在具有多个自由度的系统中，有一个项来自于单个变量的不可逆动力学，其余一系列非负项是由变量对、三元组和高阶变量组合之间的相关性贡献的。作者在噪声逻辑计算的简单模型上阐明了这种分解，并将其应用于分析视网膜对复杂动态视觉场景做出反应时的神经活动模式。研究发现，即使视觉输入没有破坏细致平衡，神经活动也会打破，而这种不可逆性主要来自于神经元对之间的相互作用。
Decomposing the Local Arrow of Time in Interacting Systems
Christopher W. Lynn et al.
Phys. Rev. Lett. 129, 118101 (2022)
10-04
集体马达驱动输运的动力学和热力学边界
分子马达协同工作以在细胞内运输货物，从一个到数百个马达牵引一个货物。尽管已经对许多特定的输运系统模型进行了探索，但对于一般输运系统的基本性能限制仍知之甚少。Leighton等人针对一类广泛的集体输运系统，利用随机热力学的工具推导出了一个比第二定律更严格的熵产率的新下界，这意味着对一般输运系统的速度、效率和精度有了新的界限。对于相同的马达，作者建立了一组解析帕累托边界。最后，作者通过模拟一个示例系统来说明这些边界和足以使其饱和的条件。
Dynamic and Thermodynamic Bounds for Collective Motor-Driven Transport
Matthew P. Leighton et al.
Phys. Rev. Lett. 129, 118102 (2022)
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