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 (6)

• Molecular Quantum Materials: Electronic Phases and Charge Dynamics in Two-Dimensional Organic Solids
• Superconductivity and Mottness in Organic Charge Transfer Materials
• Anomalously field-susceptible spin soft-matter emerging in an electric-dipole liquid candidate
• Electronic properties of the dimerized organic conductor $\kappa$-(BETS)${}_2$Mn[N(CN)${}_2$]${}_3$
• Tuning Charge Order in $\kappa$-(BEDT-TTF)${}_2$Hg(SCN)${}_2$X (X=Br, Cl) via Uniaxial Strain
• ${}^{13}$C NMR observation of a nonmagnetic charge-ordered state in the organic conductor $\kappa$-(ET)${}_2$Hg(SCN)${}_2$Cl