Joshi Lata Kh, Franke Johannes, Rath Aniket, Ares Filiberto, Murciano Sara, Kranzl Florian, Blatt Rainer, Zoller Peter, Vermersch Benoît, Calabrese Pasquale, Roos Christian F, Joshi Manoj K
Institute for Quantum Optics and Quantum Information, Austrian Academy of Sciences, Technikerstraße 21a, 6020 Innsbruck, Austria.
University of Innsbruck, Institute for Theoretical Physics, Technikerstraße 21a, 6020 Innsbruck, Austria.
Phys Rev Lett. 2024 Jul 5;133(1):010402. doi: 10.1103/PhysRevLett.133.010402.
The nonequilibrium physics of many-body quantum systems harbors various unconventional phenomena. In this Letter, we experimentally investigate one of the most puzzling of these phenomena-the quantum Mpemba effect, where a tilted ferromagnet restores its symmetry more rapidly when it is farther from the symmetric state compared to when it is closer. We present the first experimental evidence of the occurrence of this effect in a trapped-ion quantum simulator. The symmetry breaking and restoration are monitored through entanglement asymmetry, probed via randomized measurements, and postprocessed using the classical shadows technique. Our findings are further substantiated by measuring the Frobenius distance between the experimental state and the stationary thermal symmetric theoretical state, offering direct evidence of subsystem thermalization.
多体量子系统的非平衡物理蕴含着各种非常规现象。在本信函中，我们通过实验研究了这些现象中最令人费解的一种——量子姆潘巴效应，即倾斜的铁磁体在远离对称状态时比接近对称状态时更快地恢复其对称性。我们展示了在囚禁离子量子模拟器中出现这种效应的首个实验证据。通过纠缠不对称性来监测对称性破缺和恢复，通过随机测量进行探测，并使用经典影子技术进行后处理。我们通过测量实验态与静态热对称理论态之间的弗罗贝尼乌斯距离进一步证实了我们的发现，为子系统热化提供了直接证据。
