Open quantum dynamics with variational non-Gaussian states and the truncated Wigner approximation

TL;DR

This paper introduces a novel framework combining variational non-Gaussian states with quantum trajectories to simulate open quantum dynamics of spin-boson systems, benchmarking its performance against the truncated Wigner approximation.

Contribution

It develops a new method for simulating open quantum systems that integrates variational non-Gaussian states with quantum trajectories, applicable to complex spin-boson models.

Findings

The combined method accurately simulates spin-boson dynamics.

Benchmarking shows regimes where each method performs best.

Strategies for improving simulation accuracy are discussed.

Abstract

We present a framework for simulating the open dynamics of spin-boson systems by combining variational non-Gaussian states with a quantum trajectories approach. We apply this method to a generic spin-boson Hamiltonian that has both Tavis-Cummings and Holstein type couplings, and which has broad applications to a variety of quantum simulation platforms, polaritonic physics, and quantum chemistry. Additionally, we discuss how the recently developed truncated Wigner approximation for open quantum systems can be applied to the same Hamiltonian. We benchmark the performance of both methods and identify the regimes where each method is best suited to. Finally we discuss strategies to improve each technique.