Imaging phase separation near the Mott boundary in the correlated organic superconductors $\kappa$-(BEDT-TTF)${}_2$X

Abstract

Electronic phase separation consisting of the metallic and insulating domains with 50 -- 100 $\mu$m in diameter is found in the organic Mott system $\kappa$-[($h$8-BEDT-TTF)${}_{1-x}$($d$8-BEDT-TTF)${}_x$]${}_2$Cu[N(CN)${}_2$]Br by means of scanning micro-region infrared spectroscopy using the synchrotron radiation. The phase separation appears below the critical end temperature 35 -- 40 K of the first order Mott transition. The observation of the macroscopic size of the domains indicates a different class of the intrinsic electronic inhomogeneity from the nano-scale one reported in the inorganic Mott systems such as High-$T_c$ copper and manganese oxides.

4 pages, 3 figures

Cited by in corpus (2)

• Real space imaging of the metal - insulator phase separation in the band width controlled organic Mott system $\kappa$-(BEDT-TTF)${}_2$Cu[N(CN)${}_2$]Br
• Phase separation in the vicinity of the surface of $\kappa$-(BEDT-TTF)${}_2$Cu[N(CN)${}_2$]Br by fast cooling