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arXiv · 2111.13719

Probing many-body localization by excited-state VQE

Shuo Liu·Shi-Xin Zhang·Chang-Yu Hsieh·Shengyu Zhang·Hong Yao
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Abstract

Non-equilibrium physics including many-body localization (MBL) has attracted increasing attentions, but theoretical approaches of reliably studying non-equilibrium properties remain quite limited. In this Letter, we propose a systematic approach to probe MBL phases via the excited-state variational quantum eigensolver (VQE) and demonstrate convincing results of MBL on a quantum hardware, which we believe paves a promising way for future simulations of non-equilibrium systems beyond the reach of classical computations in the noisy intermediate-scale quantum (NISQ) era. Moreover, the MBL probing protocol based on excited-state VQE is NISQ-friendly, as it can successfully differentiate the MBL phase from thermal phases with relatively-shallow quantum circuits, and it is also robust against the effect of quantum noises.

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Shuo Liu, Shi-Xin Zhang, Chang-Yu Hsieh, Shengyu Zhang, Hong Yao. 2023-02-06. Probing many-body localization by excited-state VQE. https://doi.org/10.1103/physrevb.107.024204

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