Metal-Insulator Transition in the Dimerized Organic Conductor $\kappa$-(BEDT-TTF)${}_2$Hg(SCN)${}_2$Br

Abstract

The organic charge-transfer salt $\kappa$-(BEDT-TTF)${}_2$Hg(SCN)${}_2$Br is a quasi two-dimensional metal with a half-filled conduction band at ambient conditions. When cooled below $T=80$ K it undergoes a pronounced transition to an insulating phase where the resistivity increases many orders of magnitude. In order to elucidate the nature of this metal-insulator transition we have performed comprehensive transport, dielectric and optical investigations. The findings are compared with other dimerized $\kappa$-(BEDT-TTF) salts, in particular the Cl-analogue, where a charge-order transition takes place at $T_{\mathrm{CO}}=30$ K.

submitted to Physical Review B, 9 pages, 7 figures

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Cited by in corpus (1)

• Molecular Quantum Materials: Electronic Phases and Charge Dynamics in Two-Dimensional Organic Solids