Probing spin hydrodynamics on a superconducting quantum simulator

Yun-Hao Shi; Zheng-Hang Sun; Yong-Yi Wang; Zheng-An Wang; Yu-Ran Zhang; Wei-Guo Ma; Hao-Tian Liu; Kui Zhao; Jia-Cheng Song; Gui-Han Liang; Zheng-Yang Mei; Jia-Chi Zhang; Hao Li; Chi-Tong Chen; Xiaohui Song; Jieci Wang; Guangming Xue; Haifeng Yu; Kaixuan Huang; Zhongcheng Xiang; Kai Xu; Dongning Zheng; Heng Fan

doi:10.1038/s41467-024-52082-2

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arXiv · 2310.06565

Probing spin hydrodynamics on a superconducting quantum simulator

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Abstract

Characterizing the nature of hydrodynamical transport properties in quantum dynamics provides valuable insights into the fundamental understanding of exotic non-equilibrium phases of matter. Experimentally simulating infinite-temperature transport on large-scale complex quantum systems is of considerable interest. Here, using a controllable and coherent superconducting quantum simulator, we experimentally realize the analog quantum circuit, which can efficiently prepare the Haar-random states, and probe spin transport at infinite temperature. We observe diffusive spin transport during the unitary evolution of the ladder-type quantum simulator with ergodic dynamics. Moreover, we explore the transport properties of the systems subjected to strong disorder or a tilted potential, revealing signatures of anomalous subdiffusion in accompany with the breakdown of thermalization. Our work demonstrates a scalable method of probing infinite-temperature spin transport on analog quantum simulators, which paves the way to study other intriguing out-of-equilibrium phenomena from the perspective of transport.

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Yun-Hao Shi, Zheng-Hang Sun, Yong-Yi Wang, Zheng-An Wang, Yu-Ran Zhang, Wei-Guo Ma, Hao-Tian Liu, Kui Zhao, Jia-Cheng Song, Gui-Han Liang, Zheng-Yang Mei, Jia-Chi Zhang, Hao Li, Chi-Tong Chen, Xiaohui Song, Jieci Wang, Guangming Xue, Haifeng Yu, Kaixuan Huang, Zhongcheng Xiang, Kai Xu, Dongning Zheng, Heng Fan. 2023-10-10. Probing spin hydrodynamics on a superconducting quantum simulator. https://doi.org/10.1038/s41467-024-52082-2

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