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تسجيل مستخدم جديدAnomalous thermopower and Nernst effect in $rm CeCoIn_5$: entropy-current loss in precursor state
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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 $alpha_{xy}$ 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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