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arXiv · 2112.08254

Numerical evaluation and robustness of the quantum mean force Gibbs state

Yiu-Fung Chiu·Aidan Strathearn·Jonathan Keeling
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Abstract

We introduce a numerical method to determine the Hamiltonian of Mean Force (HMF) Gibbs state for a quantum system strongly coupled to a reservoir. The method adapts the Time Evolving Matrix Product Operator (TEMPO) algorithm to imaginary time propagation. By comparing the real-time and imaginary-time propagation for a generalized spin-boson model, we confirm that the HMF Gibbs state correctly predicts the steady state. We show that the numerical dynamics match the polaron master equation at strong coupling. We illustrate the potential of the imaginary-time TEMPO approach by exploring reservoir-induced entanglement between qubits.

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Yiu-Fung Chiu, Aidan Strathearn, Jonathan Keeling. 2021-12-15. Numerical evaluation and robustness of the quantum mean force Gibbs state. https://doi.org/10.1103/physreva.106.012204

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