Energy Transport in Randomly Coupled Quantum Systems: A Perturbative Approach

Tingfei Li; Runyu Chen

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arXiv · 2606.09308

Energy Transport in Randomly Coupled Quantum Systems: A Perturbative Approach

Tingfei Li·Runyu Chen

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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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BibTeX RIS

Tingfei Li, Runyu Chen. 2026-06-08. Energy Transport in Randomly Coupled Quantum Systems: A Perturbative Approach. https://arxiv.org/abs/2606.09308

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