Energy transport in randomly coupled quantum systems: A perturbative approach
Phys. Rev. D 114, 056021 – Published 22 September, 2026
DOI: https://doi.org/10.1103/nt8j-wxsb
Abstract
We study energy transport between two quantum systems coupled through a random interaction. The central feature of our approach is to model the coupling as a Gaussian random matrix, which enables a simple and systematic perturbative expansion. In the large- limit, we derive explicit expressions for the energy transfer rate and heat conductance up to second order in the coupling strength. Using spectral methods and diagrammatic expansions, we obtain the leading-order and next-to-leading-order contributions to the energy transfer rate. We illustrate our results through explicit calculations for Gaussian, constant, semicircular, and gamma densities of states.