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, Jiacheng Song, Gui-Han Liang, Zheng-Yang Mei, Jiachi Zhang, Hao Li, Chi-Tong Chen, Xiaohui Song, Jieci Wang, Guangming Xue, Haifeng Yu, Kaixuan Huang, Zhongcheng Xiang, Kai Xu, Dongning Zheng, Heng Fan
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. Quantum devices offer the potential to simulate quantum phenomena, which are otherwise computationally intractable. Here, Shi, Sun, Wang and coauthors use a superconducting quantum simulator to study spin-transport at infinite temperature.