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arXiv · 2101.08031

Observation of thermalization and information scrambling in a superconducting quantum processor

Qingling Zhu·Zheng-Hang Sun·Ming Gong·Fusheng Chen·Yu-Ran Zhang·Yulin Wu·Yangsen Ye·Chen Zha·Shaowei Li·Shaojun Guo·Haoran Qian·He-Liang Huang·Jiale Yu·Hui Deng·Hao Rong·Jin Lin·Yu Xu·Lihua Sun·Cheng Guo·Na Li·Futian Liang·Cheng-Zhi Peng·Heng Fan·Xiaobo Zhu·Jian-Wei Pan
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Abstract

Understanding various phenomena in non-equilibrium dynamics of closed quantum many-body systems, such as quantum thermalization, information scrambling, and nonergodic dynamics, is a crucial for modern physics. Using a ladder-type superconducting quantum processor, we perform analog quantum simulations of both the $XX$ ladder and one-dimensional (1D) $XX$ model. By measuring the dynamics of local observables, entanglement entropy and tripartite mutual information, we signal quantum thermalization and information scrambling in the $XX$ ladder. In contrast, we show that the $XX$ chain, as free fermions on a 1D lattice, fails to thermalize, and local information does not scramble in the integrable channel. Our experiments reveal ergodicity and scrambling in the controllable qubit ladder, and opens the door to further investigations on the thermodynamics and chaos in quantum many-body systems.

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Qingling Zhu, Zheng-Hang Sun, Ming Gong, Fusheng Chen, Yu-Ran Zhang, Yulin Wu, Yangsen Ye, Chen Zha, Shaowei Li, Shaojun Guo, Haoran Qian, He-Liang Huang, Jiale Yu, Hui Deng, Hao Rong, Jin Lin, Yu Xu, Lihua Sun, Cheng Guo, Na Li, Futian Liang, Cheng-Zhi Peng, Heng Fan, Xiaobo Zhu, Jian-Wei Pan. 2021-01-20. Observation of thermalization and information scrambling in a superconducting quantum processor. https://doi.org/10.1103/physrevlett.128.160502

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