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Science,迷信 23 JUN 2023, VOL 380, ISSUE 6651

《迷信》2023年6月23日，第380卷，出书6651期

?周论

物理学Physics

Hunting for Majoranas

追寻马约拉纳准粒子

▲ 作者
：Ali Yazdani, Felix von Oppen, Bertrand I. Halperin & Amir Yacoby

▲ 链接 ：https://www.science.org/doi/10.1126/science.ade0850

▲ 摘要：

在以前十年里
，人们支出了至关大的文导自动 ，以在新型量子质料以及器件中审核非阿贝尔准粒子。迷信这些自动的出书念头是为了证实逾越费米子以及玻色子的准粒子的量子统计 ，并为建树拓扑呵护量子比特建树根基迷信 。周论

在这篇综述中 ，文导钻研组聚焦于自动建树具备马约拉纳零模的迷信拓扑超导相。他们思考了从现有试验使掷中罗致的出书履历履历 ，这些履历履历增长着对于现有平台的周论改善以及新措施的探究  。

尽管非阿贝尔准粒子的文导尝试探测仍颇具挑战性 ，但迄今为止人们所取患上的迷信知识以及未来机缘 ，将为量子物理学这一使人欢喜规模的出书发现以及后退提供重大后劲。

▲ Abstract：

Over the past decade,周论 there have been considerable efforts to observe non-abelian quasiparticles in novel quantum materials and devices. These efforts are motivated by the goals of demonstrating quantum statistics of quasiparticles beyond those of fermions and bosons and of establishing the underlying science for the creation of topologically protected quantum bits. In this Review, we focus on efforts to create topological superconducting phases that host Majorana zero modes. We consider the lessons learned from existing experimental efforts, which are motivating both improvements to present platforms and the exploration of new approaches. Although the experimental detection of non-abelian quasiparticles remains challenging, the knowledge gained thus far and the opportunities ahead offer high potential for discovery and advances in this exciting area of quantum physics.

Mid-circuit correction of correlated phase errors using an array of spectator qubits

运用旁不雅者量子位阵列对于相关相位倾向妨碍中路校对于

▲ 作者
：K. Singh, C. E. Bradley, S. Anand, V. Ramesh, R. White & H. Bernien.

▲ 链接：https://www.science.org/doi/10.1126/science.ade5337

▲ 摘要 ：

扩展总是简略侵蚀的量子处置器是一项难题挑战 。尽管量子纠错最终保障了容错操作，但所需的庞大批子位数以及过错阈值使人望而生畏。在一项填补协议中 ，共置辅助“旁不雅者”量子位充任噪声的原位探针 ，并实现对于数据量子位过错的实时 、相关更正。

钻研组运用铯旁不雅者量子位阵列来校对于铷数据量子位阵列上的相关相位倾向  。经由散漫挨次读出、数据处置以及前馈操作，这些相关倾向在量子电路的实施中有所飞腾。

该协议普遍适用于量子信息平台，建树了扩展中性原子量子处置器的关键工具：原子阵列的中路读出、实时处置以及前馈，以及原子量子位的相关中路重装。

▲ Abstract ：

Scaling up invariably error-prone quantum processors is a formidable challenge. Although quantum error correction ultimately promises fault-tolerant operation, the required qubit overhead and error thresholds are daunting. In a complementary proposal, colocated, auxiliary “spectator” qubits act as in situ probes of noise and enable real-time, coherent corrections of data qubit errors. We used an array of cesium spectator qubits to correct correlated phase errors on an array of rubidium data qubits. By combining in-sequence readout, data processing, and feedforward operations, these correlated errors were suppressed within the execution of the quantum circuit. The protocol is broadly applicable to quantum information platforms and establishes key tools for scaling neutral-atom quantum processors: mid-circuit readout of atom arrays, real-time processing and feedforward, and coherent mid-circuit reloading of atomic qubits.

质料迷信Materials Science

Superconducting vortices carrying a temperature-dependent fraction of the flux quantum

照料通量量子温度相关分数的超导涡旋

▲ 作者：Yusuke Iguchi, Kunihiro Kihou, Chul-Ho Lee, Mats Barkman, Andrea L. Benfenati, Vadim Grinenko, et al.

▲ 链接：https://www.science.org/doi/10.1126/science.abp9979

▲ 摘要 ：

磁场经由组成量子涡旋（困绕的磁通量即是磁通量量子）穿透II型体超导体 。磁通量量子是一个只依赖于根基常数的普过多 。

钻研组运用扫描超导量子干涉装置（SQUID）磁强计钻研了空穴过异化Ba1?xKxFe2As2 （x = 0.77）中的单独涡旋。在良多中间 
，钻研组审核到的涡旋只照料部份磁通量量子
，其巨细随温度不断变更。

钻研组揭示了这些涡旋的可挪移性以及可操作性 ，并将其批注为具备非普过多子化（分数）磁通量的量子涡旋，其巨细由多组分超导体的温度相关参数抉择。

▲ Abstract：

Magnetic field penetrates type-II bulk superconductors by forming quantum vortices that enclose a magnetic flux equal to the magnetic flux quantum. The flux quantum is a universal quantity that depends only on fundamental constants. In this study, we investigated isolated vortices in the hole-overdoped Ba1?xKxFe2As2  (x = 0.77) by using scanning superconducting quantum interference device (SQUID) magnetometry. In many locations, we observed objects that carried only part of a flux quantum, with a magnitude that varied continuously with temperature. We demonstrated mobility and manipulability of these objects and interpreted them as quantum vortices with nonuniversally quantized (fractional) magnetic flux whose magnitude is determined by the temperature-dependent parameters of a multicomponent superconductor.

Deformable hard tissue with high fatigue resistance in the hinge of bivalve Cristaria plicata

双壳纲褶纹冠蚌铰链中具备高抗疲惫性的可变形硬机关

▲ 作者：Xiang-Sen Meng, Li-Chuan Zhou, Lei Liu, Yin-Bo Zhu, Yu-Feng Meng, Dong-Chang Zheng, et al.

▲ 链接：https://www.science.org/doi/10.1126/science.ade2038

▲ 摘要：

双壳纲植物的外壳铰链在其一生中可接受数十万次一再的双壳开合行动 。

钻研组品评辩说了双壳纲褶纹冠蚌铰链中矿化机关的分层妄想，这使患上机关具备可变形性以及抗疲惫性
，从而奠基了一再行动能耐的根基。这种折叠的扇形机关由嵌入弹性基质中的径向部署的脆性文石纳米线组成，可将外部径向载荷转化为周向变形  。

软硬复合宏不雅妄想可抑制机关内的应力会集 。沿纳米线纵向倾向的相关纳米孪晶界削减了其抗笔直断裂的能耐 。这种不艰深的生物矿物经由多尺度妄想妄想运用了每一种成份的固有特色，为抗疲惫妄想质料的演化提供了新见识。

▲ Abstract ：

The hinge of bivalve shells can sustain hundreds of thousands of repeating opening-and-closing valve motions throughout their lifetime. We studied the hierarchical design of the mineralized tissue in the hinge of the bivalve Cristaria plicata, which endows the tissue with deformability and fatigue resistance and consequently underlies the repeating motion capability. This folding fan–shaped tissue consists of radially aligned, brittle aragonite nanowires embedded in a resilient matrix and can translate external radial loads to circumferential deformation. The hard-soft complex microstructure can suppress stress concentration within the tissue. Coherent nanotwin boundaries along the longitudinal direction of the nanowires increase their resistance to bending fracture. The unusual biomineral, which exploits the inherent properties of each component through multiscale structural design, provides insights into the evolution of antifatigue structural materials.

化学Chemistry

Facile mechanochemical cycloreversion of polymer cross-linkers enhances tear resistance

聚合物交联剂的浅易机械化学裂环增强了抗撕裂性

▲ 作者：Shu Wang, Yixin Hu, Tatiana B. Kouznetsova, Liel Sapir, Danyang Chen, Abraham Herzog-Arbeitman, et al.

▲ 链接 ：https://www.science.org/doi/10.1126/science.adg3229

▲ 摘要：

共价聚合物收集的机械功能个别源于聚合物链的永世收尾衔接或者交联 ，更易断裂的份子衔接物可能会发生撕裂所需能量更少的质料。

钻研组报道称，基于环丁烷的力敏基团交联剂突破了力触发的裂环熏染，发生的聚合物收集韧性是传统相似物的九倍。这种反映归因于长而强的主聚合物链以及交联剂剪切力的散漫 ，在相同光阴尺度下，这些力比比力交联剂小约五倍。

增强的韧性不与非共价交联相关的滞后天气，且在两种差距的丙烯酸酯弹性体中，在疲惫以及恒定位移速率张力下，以及在凝胶以及弹性体中均审核到该韧性。

▲ Abstract：

The mechanical properties of covalent polymer networks often arise from the permanent end-linking or cross-linking of polymer strands, and molecular linkers that break more easily would likely produce materials that require less energy to tear. We report that cyclobutane-based mechanophore cross-linkers that break through force-triggered cycloreversion lead to networks that are up to nine times as tough as conventional analogs. The response is attributed to a combination of long, strong primary polymer strands and cross-linker scission forces that are approximately fivefold smaller than control cross-linkers at the same timescales. The enhanced toughness comes without the hysteresis associated with noncovalent cross-linking, and it is observed in two different acrylate elastomers, in fatigue as well as constant displacement rate tension, and in a gel as well as elastomers.

地球迷信Earth Science

Large herbivore diversity slows sea ice–associated decline in arctic tundra diversity

大型食草植物的多样性缓解了北极苔原海冰相关的多样性着落

▲ 作者 ：Eric Post, Elina Kaarlej?rvi, Marc Macias-Fauria, David A. Watts, Pernille Sporon B?ving, Sean M. P. Cahoon, et al.

▲ 链接 ：https://www.science.org/doi/10.1126/science.add2679

▲ 摘要：

由于搜罗天气欺压在内的多种人类压力因素，全天下生物多样性正不才降 。可是，部份多样性趋向在某些分类群中并不不同 ，迷糊了部份历程对于全天下方式的贡献 。

在一项为期15年的试验中，随着天气变暖 ，搜罗植物 、真菌以及地衣的北极苔原多样性有所着落，已经知会影响苔原植被组成的大型食草植物被清扫在外 。由于妨碍季的布景温度随着海冰的削减而回升
，不论试验处置若何，苔原多样性都不才降。

可是 ，有大型食草植物时 ，多样性着落的速率比不大型食草植物时慢。这种差距与大型食草植物实用多样性的削减无关  ，由于此前数目丰硕的北美驯鹿削减了，麝牛数目削减。增长食草植物多样性的自动，如重新毁林 ，或者有助于减轻天气变暖对于苔原多样性的影响 。

▲ Abstract：

Biodiversity is declining globally in response to multiple human stressors, including climate forcing. Nonetheless, local diversity trends are inconsistent in some taxa, obscuring contributions of local processes to global patterns. Arctic tundra diversity, including plants, fungi, and lichens, declined during a 15-year experiment that combined warming with exclusion of large herbivores known to influence tundra vegetation composition. Tundra diversity declined regardless of experimental treatment, as background growing season temperatures rose with sea ice loss. However, diversity declined slower with large herbivores than without them. This difference was associated with an increase in effective diversity of large herbivores as formerly abundant caribou declined and muskoxen increased. Efforts that promote herbivore diversity, such as rewilding, may help mitigate impacts of warming on tundra diversity.