Numerical evaluation and robustness of the quantum mean force Gibbs state

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.

Citation

Chiu , Y-F , Strathearn , A & Keeling , J 2022 , ' Numerical evaluation and robustness of the quantum mean force Gibbs state ' , Physical Review. A, Atomic, molecular, and optical physics , vol. 106 , no. 1 , 012204 . https://doi.org/10.1103/PhysRevA.106.012204

Publication

Physical Review. A, Atomic, molecular, and optical physics

Status

Peer reviewed

DOI

https://doi.org/10.1103/PhysRevA.106.012204

ISSN

1050-2947

Type

Journal article

Rights

Copyright © 2022 American Physical Society. This work has been made available online in accordance with publisher policies or with permission. Permission for further reuse of this content should be sought from the publisher or the rights holder. This is the author created accepted manuscript following peer review and may differ slightly from the final published version. The final published version of this work is available at https://doi.org/10.1103/PhysRevA.106.012204.

Description

Funding: Y.F.C. acknowledges funding from the St Andrews Undergraduate Research Assistant Scheme, the School of Physics and Astronomy Student-Staff Council vacation awards, and the University of St Andrews Physics Trust. J.K. acknowledges funding from EPSRC (EP/T014032/1).

Collections

University of St Andrews Research

URI

http://hdl.handle.net/10023/25575