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arXiv · 2404.01061

Wiedemann-Franz law violation domain for graphene and nonrelativistic systems

Thandar Zaw Win·Cho Win Aung·Gaurav Khandal·Sabyasachi Ghosh
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Abstract

A systematic non-fluid to fluid transition framework and comparative research on Lorenz ratios for graphene and nonrelativistic systems have been studied to identify their Wiedemann-Franz law violation domain. Here, Lorenz ratio is defined as thermal conductivity divided by electrical conductivity times temperature times Lorenz number. In non-fluid framework, Lorenz ratio become exactly one, which means that the Wiedemann-Franz is obeyed within a Fermi Liquid domain. When one enters from Fermi Liquid to Dirac Fluid domain, Lorenz ratio becomes less than one in non-fluid framework but in fluid framework, it always remain greater than one for both domain. By compiling our outcomes and connecting with experimental data, a non-fluid to fluid transition framework is expected during the transition from Fermi Liquid to Dirac Fluid domain.

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Thandar Zaw Win, Cho Win Aung, Gaurav Khandal, Sabyasachi Ghosh. 2024-04-01. Wiedemann-Franz law violation domain for graphene and nonrelativistic systems. https://doi.org/10.1142/s0217979225501826

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