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arXiv · 1103.1158

Numerical Simulation of the Nernst Effect in Extreme Type-II Superconductors: A Negative Nernst Signal and its Noise Power Spectra

Sangwoo S. Chung·Paata Kakashvili·C. J. Bolech
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Abstract

Recently, different transport coefficients have been measured in High-Tc superconductors to pinpoint the nature of the pseudogap phase. In particular, the thermoelectric coefficients received a considerable attention both theoretically and experimentally. We numerically simulate the Nernst effect in extreme type-II superconductors using the time-dependent Ginzburg-Landau equations. We report the sign reversal of the thermoelectric coefficient, alpha_xy, at temperatures close to the mean-field transition temperature, Tc^{MF}(H), which qualitatively agrees with recent experiments on high-Tc materials. We also discuss the noise power spectrum of alpha_xy, which shows 1/f^beta behavior. Based on this observation, we propose an experiment to distinguish among different regimes of vortex dynamics by measuring the noise correlations of the Nernst signal.

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Sangwoo S. Chung, Paata Kakashvili, C. J. Bolech. 2012-12-28. Numerical Simulation of the Nernst Effect in Extreme Type-II Superconductors: A Negative Nernst Signal and its Noise Power Spectra. https://doi.org/10.1103/physrevb.86.134525

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