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arXiv · 1811.05431

Fermi- to non-Fermi-liquid crossover and Kondo transition in two-dimensional Cu$_{2/3}$V$_{1/3}$V$_2$S$_4$

A. Gauzzi·H. Moutaabbid·Y. Klein·G. Loupias·V. Hardy
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Abstract

By means of a specific heat ($C$) and electrical resistivity ($\varrho$) study, we give evidence of a pronounced Fermi liquid (FL) behavior with sizable mass renormalization, $m^{\ast}/m = 30$, up to unusually high temperatures $\sim$70 K in the layered system Cu$_{2/3}$V$_{1/3}$V$_2$S$_4$. At low temperature, a marked upturn of both $C$ and $\varrho$ is suppressed by magnetic field, which suggests a picture of Kondo coupling between conduction electrons in the VS$_2$ layers and impurity spins of the V$^{3+}$ ions located between layers. This picture opens the possibility of controlling electronic correlations and the FL to non-FL crossover in simple layered materials. For instance, we envisage that the coupling between layers provided by the impurity spins may realize a two-channel Kondo state.

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A. Gauzzi, H. Moutaabbid, Y. Klein, G. Loupias, V. Hardy. 2018-11-13. Fermi- to non-Fermi-liquid crossover and Kondo transition in two-dimensional Cu$_{2/3}$V$_{1/3}$V$_2$S$_4$. https://doi.org/10.1088/1361-648x%2Fab1d9b

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