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arXiv:2606.09308 · Physical review. D/Physical review. D.

Energy Transport in Randomly Coupled Quantum Systems: A Perturbative Approach

Tingfei Li, Runyu Chen

quant-phcond-mat.stat-mechhep-thSubmitted Jun 8, 2026• Announced Jun 9, 2026• 0 citations
v1 · Jun 8, 2026v2 · Jun 20, 2026
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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-$N$ 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- 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.

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28 pages

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