Lorentz ratio of a compensated metal

Article

关键词: TRANSPORT-COEFFICIENTS;    FERMI-LIQUID;    RESISTIVITY;   

DOI  :  10.1103/PhysRevB.98.245134

来源: SCIE

【 摘 要 】

A violation of the Wiedemann-Franz law in a metal can be quantified by comparing the Lorentz ratio, L =kappa rho/T, where kappa is the thermal conductivity and rho is the electrical resistivity, with the universal Sommerfeld constant, L-0 = (pi(2)/3 )(k(B)/e)(2). We obtain the Lorentz ratio of a clean compensated metal with intercarrier interaction as the dominant scattering mechanism by solving exactly the system of coupled integral Boltzmann equations. The Lorentz ratio is shown to assume a particular simple form in the forward-scattering limit: L/L-0 = (Theta(2))over bar/2, where Theta is the scattering angle. In this limit, L/L-0 can be arbitrarily small. We also show how the same result can be obtained without the benefit of an exact solution. We discuss how a strong downward violation of the Wiedemann-Franz law in a type-II Weyl semimetal WP2 can be explained within our model.

【 授权许可】

Free