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Transport criticality of the first-order Mott transition in a quasi-two-dimensional organic conductor, $κ$-(BEDT-TTF)$_{2}$Cu[N(CN)$_{2}$]Cl

F. Kagawa·T. Itou·K. Miyagawa·K. Kanoda
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Abstract

An organic Mott insulator, $κ$-(BEDT-TTF)$_{2}$Cu[N(CN)$_{2}$]Cl, was investigated by resistance measurements under continuously controllable He gas pressure. The first-order Mott transition was demonstrated by observation of clear jump in the resistance variation against pressure. Its critical endpoint at 38 K is featured by vanishing of the resistive jump and critical divergence in pressure derivative of resistance, $|\frac{1}{R}\frac{\partial R}{\partial P}|$, which are consistent with the prediction of the dynamical mean field theory and have phenomenological correspondence with the liquid-gas transition. The present results provide the experimental basis for physics of the Mott transition criticality.

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F. Kagawa, T. Itou, K. Miyagawa, K. Kanoda. 2003-09-18. Transport criticality of the first-order Mott transition in a quasi-two-dimensional organic conductor, $κ$-(BEDT-TTF)$_{2}$Cu[N(CN)$_{2}$]Cl. https://doi.org/10.1103/physrevb.69.064511

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