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Vortex Origin of Tricritical Point in Ginzburg-Landau Theory

H. Kleinert
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Abstract

Motivated by recent experimental progress in the critical regime of high-$T_c$ superconductors we show how the tricritical point in a superconductor can be derived from the Ginzburg-Landau theory as a consequence of vortex fluctuations. Our derivation explains why usual renormalization group arguments always produce a first-order transition, in contrast to experimental evidence and Monte Carlo simulations.

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H. Kleinert. 2005-09-16. Vortex Origin of Tricritical Point in Ginzburg-Landau Theory. https://doi.org/10.1209/epl%2Fi2006-10029-5

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