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arXiv · 2604.12943

Spectroscopy of Heat Transport and Violation of the Wiedemann--Franz Law in a GaAs Hydrodynamic Mesoscopic Channel

Yu. A. Pusep·M. A. T. Patricio·M. M. Glazov·V. A. Oliveira·M. D. Teodoro·A. D. Levin·A. K. Bakarov·G. M. Gusev
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Abstract

The Wiedemann--Franz law, which determines the universality of the ratio of thermal conductivity to electrical conductivity, is studied in the hydrodynamic electron transport regime, where electron--electron scattering predominates over scattering by disorder. In this case, the different relaxation of electric and thermal currents can lead to a violation of the Wiedemann--Franz law, which is expected to be even more pronounced in mesoscopic electron systems. This paper reports the propagation of hot electrons in a GaAs hydrodynamic narrow channel, studied using micrometer-resolution photoluminescence thermometry. A temperature dependence of the Lorenz number was obtained, indicating a violation of the Wiedemann--Franz law. The important role of narrow constrictions in this violation was also demonstrated, and theoretical arguments are presented.

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Yu. A. Pusep, M. A. T. Patricio, M. M. Glazov, V. A. Oliveira, M. D. Teodoro, A. D. Levin, A. K. Bakarov, G. M. Gusev. 2026-04-14. Spectroscopy of Heat Transport and Violation of the Wiedemann--Franz Law in a GaAs Hydrodynamic Mesoscopic Channel. https://doi.org/10.1038/s41598-026-45858-7

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