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arXiv · 2603.11713

Intrinsic violation of the Wiedemann-Franz law in interacting systems

YuanDong Wang·Zhen-Gang Zhu
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Abstract

The Wiedemann-Franz (WF) law dictates a universal ratio between thermal and electrical conductivities, is widely obeyed by Fermi liquid systems. Here, we identify a fundamental yet often overlooked, thermodynamic mechanism for the violation of WF law: the temperature-dependent renormalization of the electronic band structure. We demonstrate that the interaction-induced energy drift $\partial\epsilon_k/\partial T$, acts as an effective driving force that fundamentally decouples heat transport from charge transport. We derive a generalized transport relation linking the Lorenz ratio deviation directly to the thermoelectric response. Our findings provide a unified framework for understanding thermal transport in interacting topological phases and suggest the Lorenz ratio as a probe for distinguishing topological robustness from Fermi liquid instabilities.

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YuanDong Wang, Zhen-Gang Zhu. 2026-03-12. Intrinsic violation of the Wiedemann-Franz law in interacting systems. https://arxiv.org/abs/2603.11713

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