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arXiv · 2507.11675

Dynamics Simulation of Arbitrary Non-Hermitian Systems Based on Quantum Monte Carlo

Xiaogang Li·Kecheng Liu·Qiming Ding
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Abstract

Non-Hermitian quantum systems exhibit unique properties and hold significant promise for diverse applications, yet their dynamical simulation poses a particular challenge due to intrinsic openness and non-unitary evolution. Here, we introduce a hybrid classical-quantum algorithm based on Quantum Monte Carlo (QMC) for simulating the dynamics of arbitrary time-dependent non-Hermitian systems. Notably, this approach constitutes a natural extension of the quantum imaginary-time evolution (QITE) algorithm. This algorithm combines the advantages of both classical and quantum computation and exhibits good applicability and adaptability, making it promising for simulating arbitrary non-Hermitian systems such as PT-symmetric systems, non-physical processes, and open quantum systems. To validate the algorithm, we applied it to the dynamic simulation of open quantum systems and achieved the desired results.

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Xiaogang Li, Kecheng Liu, Qiming Ding. 2025-07-15. Dynamics Simulation of Arbitrary Non-Hermitian Systems Based on Quantum Monte Carlo. https://arxiv.org/abs/2507.11675

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