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arXiv · 0704.1970

Thermoelectric response near a quantum critical point: the case of CeCoIn5

K. Izawa·K. Behnia·Y. Matsuda·H. Shishido·R. Settai·Y. Onuki·J. Flouquet
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Abstract

We present a study of thermoelectric coefficients in CeCoIn_5 down to 0.1 K and up to 16 T in order to probe the thermoelectric signatures of quantum criticality. In the vicinity of the field-induced quantum critical point, the Nernst coefficient nu exhibits a dramatic enhancement without saturation down to lowest measured temperature. The dimensionless ratio of Seebeck coefficient to electronic specific heat shows a minimum at a temperature close to threshold of the quasiparticle formation. Close to T_c(H), in the vortex-liquid state, the Nernst coefficient behaves anomalously in puzzling contrast with other superconductors and standard vortex dynamics.

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K. Izawa, K. Behnia, Y. Matsuda, H. Shishido, R. Settai, Y. Onuki, J. Flouquet. 2007-10-09. Thermoelectric response near a quantum critical point: the case of CeCoIn5. https://doi.org/10.1103/physrevlett.99.147005

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