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arXiv · 0705.0928

Anomalous thermopower and Nernst effect in $\rm CeCoIn_5$: entropy-current loss in precursor state

Y. Onose·Lu Li·C. Petrovic·N. P. Ong
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Abstract

The heavy-electron superconductor CeCoIn$_5$ exhibits a puzzling precursor state above its superconducting critical temperature at $T_c$ = 2.3 K. The thermopower and Nernst signal are anomalous. Below 15 K, the entropy current of the electrons undergoes a steep decrease reaching $\sim$0 at $T_c$. Concurrently, the off-diagonal thermoelectric current $α_{xy}$ is enhanced. The delicate sensitivity of the zero-entropy state to field implies phase coherence over large distances. The prominent anomalies in the thermoelectric current contrast with the relatively weak effects in the resistivity and magnetization.

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Y. Onose, Lu Li, C. Petrovic, N. P. Ong. 2007-05-07. Anomalous thermopower and Nernst effect in $\rm CeCoIn_5$: entropy-current loss in precursor state. https://doi.org/10.1209/0295-5075/79/17006

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