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Mott Transition vs Multicritical Phenomenon of Superconductivity and Antiferromagnetism -- Application to $κ$-(BEDT-TTF)$_2$X --

Shigeki Onoda·Naoto Nagaosa
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Abstract

Interplay between the Mott transition and the multicritical phenomenon of d-wave superconductivity (SC) and antiferromagnetism (AF) is studied theoretically. We describe the Mott transition, which is analogous to a liquid-gas phase transition, in terms of an Ising-type order parameter $η$. We reveal possible mean-field phase diagrams produced by this interplay. Renormalization group analysis up to one-loop order gives flows of coupling constants, which in most cases lead to fluctuation-induced first-order phase transitions even when the SO(5) symmetry exists betwen the SC and AF. Behaviors of various physical quantities around the Mott critical point are predicted. Experiments in $κ$-(BEDT-TTF)$_2$X are discussed from this viewpoint.

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Shigeki Onoda, Naoto Nagaosa. 2003-08-05. Mott Transition vs Multicritical Phenomenon of Superconductivity and Antiferromagnetism -- Application to $κ$-(BEDT-TTF)$_2$X --. https://doi.org/10.1143/jpsj.72.2445

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