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arXiv · 2407.02617

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

Liam J. Bond·Bas Gerritsen·Jiří Minář·Jeremy T. Young·Johannes Schachenmayer·Arghavan Safavi-Naini
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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.

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Liam J. Bond, Bas Gerritsen, Jiří Minář, Jeremy T. Young, Johannes Schachenmayer, Arghavan Safavi-Naini. 2024-07-02. Open quantum dynamics with variational non-Gaussian states and the truncated Wigner approximation. https://doi.org/10.1063/5.0226268

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