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Mott Transition from a Spin Liquid to a Fermi Liquid in the Spin-Frustrated Organic Conductor kappa-(ET)2Cu2(CN)3

Y. Kurosaki·Y. Shimizu·K. Miyagawa·K. Kanoda·G. Saito
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Abstract

Pressure-temperature phase diagram of the organic Mott insulator $κ$-(ET)$_2$Cu$_2$(CN)$_3$, a model system of the spin liquid on triangular lattice, has been investigated by $^1$H NMR and resistivity measurements. The spin-liquid phase is persistent before the Mott transition to the metal or superconducting phase under pressure. At the Mott transition, the spin fluctuations are rapidly suppressed and the Fermi-liquid features are observed in the temperature dependence of the spin-lattice relaxation rate and resistivity. The characteristic curvature of Mott boundary in the phase diagram highlights a crucial effect of the spin frustration on the Mott transition.

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Y. Kurosaki, Y. Shimizu, K. Miyagawa, K. Kanoda, G. Saito. 2005-10-19. Mott Transition from a Spin Liquid to a Fermi Liquid in the Spin-Frustrated Organic Conductor kappa-(ET)2Cu2(CN)3. https://doi.org/10.1103/physrevlett.95.177001

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