Theoretical Description of Nearly Discontinuous Transition in Superconductors with Paramagnetic Depairing

Hiroto Adachi; Shigeru Koikegami; Ryusuke Ikeda

doi:10.1143/jpsj.72.2460

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Theoretical Description of Nearly Discontinuous Transition in Superconductors with Paramagnetic Depairing

Hiroto Adachi·Shigeru Koikegami·Ryusuke Ikeda

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Abstract

Based on a theoretical argument and Monte Carlo simulations of a Ginzburg-Landau model derived microscopically, it is argued that, in type-II superconductors where {\it both} the paramagnetic {\it and} orbital depairings are important, a strong first-order transition (FOT) at $H_{c2}$ expected in the mean field (MF) approximation never occurs in real systems and changes due to the fluctuation into a crossover. The present result explains why a {\it nearly} discontinuous crossover at $H_{c2}$ with {\it no} intrinsic hysteresis is observed only in a clean superconducting material with a singlet pairing and a high condensation energy such as CeCoIn$_5$.

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Hiroto Adachi, Shigeru Koikegami, Ryusuke Ikeda. 2003-09-30. Theoretical Description of Nearly Discontinuous Transition in Superconductors with Paramagnetic Depairing. https://doi.org/10.1143/jpsj.72.2460

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