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arXiv · 2506.01930

Statistical Interaction Driven Thermoelectricity and Violation of Wiedemann-Franz Law

Sampurna Karmakar·Amulya Ratnakar·Sourin Das
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Abstract

Quantum transport anomalies in systems obeying Haldane-Wu fractional exclusion statistics, characterized by the statistical interactions parameter $g$ are investigated. We identify particle-hole symmetry breaking of the Haldane-Wu distribution function via its deviations of the maximum entropy ($\mathcal{S}_{g}^{max}$), evaluated at the chemical potential, from the value ${k_B} \ln 2$ (a value that holds only at the free fermion limit, $g=1$). A duality relation, $g\,\mathcal{S}_{g}^{max}=\mathcal{S}_{1/g}^{max}$, quantifying the degree of violation is obtained. This symmetry breaking manifests in transport phenomena as: significant violations of the Wiedemann-Franz law arising for $g>1$ (but remain absent for $g\leq 1$) across a broad temperature range. Moreover, the thermoelectric figure of merit $ZT$ is substantially enhanced for $g>1$ and suppressed for $g<1$, indicating new routes to optimize energy conversion. These results deepen the understanding of the interplay between equilibrium statistics and transport, suggesting avenues for engineering advanced thermoelectric materials.

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Sampurna Karmakar, Amulya Ratnakar, Sourin Das. 2025-06-02. Statistical Interaction Driven Thermoelectricity and Violation of Wiedemann-Franz Law. https://arxiv.org/abs/2506.01930

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