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Giant Nernst effect in a Kondo lattice close to a quantum critical point

R. Bel·K. Behnia·Y. Nakajima·K. Izawa·Y. Matsuda·H. Shishido·R. Settai·Y. Onuki
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Abstract

We present a study of Nernst and Seebeck coefficients of the heavy-fermion superconductor CeCoIn$_{5}$. Below 18 K, concomitant with a field-dependent Seebeck coefficient, a large sub-linear Nernst signal emerges with a magnitude drastically exceeding what is expected for a multi-band Fermi-liquid metal. In the mixed state, in contrast with all other superconductors studied before, this signal overwhelms the one associated with the motion of superconducting vortices. The results point to a hitherto unknown source of transverse thermoelectricity in strongly interacting electrons.

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R. Bel, K. Behnia, Y. Nakajima, K. Izawa, Y. Matsuda, H. Shishido, R. Settai, Y. Onuki. 2003-11-20. Giant Nernst effect in a Kondo lattice close to a quantum critical point. https://doi.org/10.1103/physrevlett.92.217002

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