Quantum dynamics in multiple baths: Initial baths separability condition for noninterference

We use a master equation to provide a proof of interference between noninteracting baths on a system’s reduced dynamics, agreeing with a result in Phys. Rev. A 89, 042117 (2014)1050-294710.1103/PhysRevA.89.042117. Here, we provide a formula for the details of leading-order interference. We illustrat...

Full description

Saved in:
Bibliographic Details
Main Authors: Li Yu, Eric J. Heller
Format: Article
Language:English
Published: American Physical Society 2025-08-01
Series:Physical Review Research
Online Access:http://doi.org/10.1103/rd78-ywr8
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:We use a master equation to provide a proof of interference between noninteracting baths on a system’s reduced dynamics, agreeing with a result in Phys. Rev. A 89, 042117 (2014)1050-294710.1103/PhysRevA.89.042117. Here, we provide a formula for the details of leading-order interference. We illustrate the use of such interference toward suppressing (even freezing) decoherence with a simplest example and identify what determines the extent of decoherence suppression. However, we find that interference of baths vanishes (up to second order) as long as the baths are initially separable, thereby identifying a “low-bar” condition for noninterference. This finding provides strong justification for the widely used “additive assumption” in weak coupling regime. We discuss how this noninterference finding sheds light on the “puzzle” of vanishing second-order interference in the joint scenario of quantum and classical noises in arXiv:2004.13901. We also provide a general proof of interference between two baths under stochastic coupling, in contrast to the study of deterministic coupling in the literature. We demonstrate decoherence suppression with an example of a central spin stochastically coupled to two environmental spins. We find that two baths will cease to interfere (up to second order) if the two baths are initially separable and the system’s stochastic coupling strengths with the two baths are uncorrelated.
ISSN:2643-1564