Adaptive variational simulation for open quantum systems

TL;DR

This paper introduces an adaptive variational quantum algorithm tailored for simulating open quantum systems governed by the Lindblad equation, demonstrating its efficiency and scalability on current quantum hardware.

Contribution

It presents a novel adaptive variational algorithm that efficiently simulates open quantum systems and maintains accuracy through dynamic operator addition.

Findings

Algorithm shows good agreement with exact solutions on simulators and real hardware.

Resource scaling is polynomial with system size and accuracy.

Near-future quantum processors can simulate open quantum systems effectively.

Abstract

Emerging quantum hardware provides new possibilities for quantum simulation. While much of the research has focused on simulating closed quantum systems, the real-world quantum systems are mostly open. Therefore, it is essential to develop quantum algorithms that can effectively simulate open quantum systems. Here we present an adaptive variational quantum algorithm for simulating open quantum system dynamics described by the Lindblad equation. The algorithm is designed to build resource-efficient ansatze through the dynamical addition of operators by maintaining the simulation accuracy. We validate the effectiveness of our algorithm on both noiseless simulators and IBM quantum processors and observe good quantitative and qualitative agreement with the exact solution. We also investigate the scaling of the required resources with system size and accuracy and find polynomial behavior. Our results demonstrate that near-future quantum processors are capable of simulating open quantum systems.