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arXiv · 2602.21879

Quantum Error Mitigation Simulates General Non-Hermitian Dynamics

Hiroki Kuji·Suguru Endo·Tetsuro Nikuni·Ryusuke Hamazaki·Yuichiro Matsuzaki
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Abstract

While non-Hermitian Hamiltonians enable exotic dynamical phenomena, implementing their nonunitary time evolution on near-term quantum devices remains challenging. We propose a hardware-friendly protocol that simulates non-Hermitian dynamics without ancillas, controlled time evolution, or continuous monitoring. The protocol combines a Gorini-Kossakowski-Sudarshan-Lindblad (GKSL) evolution via classical Gaussian white-noise averaging with stochastic quantum error mitigation (QEM) to cancel the jump contribution at the level of expectation values. The mitigation layer uses only single-qubit operations. We validate the method through numerical simulations of an asymmetric-hopping model and an open {\it XXZ} spin chain with non-Hermitian boundary fields. Our work provides a programmable and ancilla-free framework for investigating exotic dynamics beyond the class of completely positive and trace-preserving dynamics using QEM.

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Hiroki Kuji, Suguru Endo, Tetsuro Nikuni, Ryusuke Hamazaki, Yuichiro Matsuzaki. 2026-02-25. Quantum Error Mitigation Simulates General Non-Hermitian Dynamics. https://arxiv.org/abs/2602.21879

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