Quantum Error Mitigation Simulates General Non-Hermitian Dynamics

TL;DR

This paper introduces a hardware-efficient quantum error mitigation protocol to simulate non-Hermitian dynamics on near-term devices, enabling exploration of exotic quantum phenomena without complex controls.

Contribution

It presents a novel, ancilla-free method combining classical noise averaging and stochastic QEM to simulate non-Hermitian evolution without continuous monitoring or controlled gates.

Findings

Validated through numerical simulations of asymmetric hopping models

Demonstrates ancilla-free implementation of non-Hermitian dynamics

Provides a programmable framework for exotic quantum phenomena

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 continuous monitoring. Gorini-Kossakowski-Sudarshan-Lindblad (GKSL) evolution via classical Gaussian white-noise averaging and to subsequently cancel the quantum-jump contribution at the level of the measured observable using stochastic quantum error mitigation (QEM). The scheme requires no ancillas or controlled time-evolution, while the mitigation layer uses only single-qubit operations. We validate the method through numerical simulations of a model with asymmetric hopping, interaction, and disorder. Our work provides a programmable and ancilla-free framework investigating exotic dynamics that are not completely-positive and trace-preserving using QEM.