Many-body Hilbert space scarring on a superconducting processor
Abstract
Quantum many-body scarring (QMBS) -- a recently discovered form of weak ergodicity breaking in strongly-interacting quantum systems -- presents opportunities for mitigating thermalization-induced decoherence in quantum information processsing. However, the existing experimental realizations of QMBS are based on kinetically-constrained systems where an emergent dynamical symmetry "shields" such states from the thermalizing bulk of the spectrum. Here, we experimentally realize a distinct kind of QMBS phenomena by approximately decoupling a part of the many-body Hilbert space in the computational basis. Utilizing a programmable superconducting processor with 30 qubits and tunable couplings, we realize Hilbert space scarring in a non-constrained model in different geometries, including a linear chain as well as a quasi-one-dimensional comb geometry. By performing full quantum state tomography on 4-qubit subsystems, we provide strong evidence for QMBS states by measuring qubit population dynamics, quantum fidelity and entanglement entropy following a quench from initial product states. Our experimental findings broaden the realm of QMBS mechanisms and pave the way to exploiting correlations in QMBS states for applications in quantum information technology.
Cite
@article{arxiv.2201.03438,
title = {Many-body Hilbert space scarring on a superconducting processor},
author = {Pengfei Zhang and Hang Dong and Yu Gao and Liangtian Zhao and Jie Hao and Qiujiang Guo and Jiachen Chen and Jinfeng Deng and Bobo Liu and Wenhui Ren and Yunyan Yao and Xu Zhang and Shibo Xu and Ke Wang and Feitong Jin and Xuhao Zhu and Hekang Li and Chao Song and Zhen Wang and Fangli Liu and Zlatko Papić and Lei Ying and H. Wang and Ying-Cheng Lai},
journal= {arXiv preprint arXiv:2201.03438},
year = {2023}
}