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Imaging phase separation near the Mott boundary in the correlated organic superconductors $κ$-(BEDT-TTF)$_{2}$X

T. Sasaki·N. Yoneyama·N. Kobayashi·Y. Ikemoto·H. Kimura
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Abstract

Electronic phase separation consisting of the metallic and insulating domains with 50 -- 100 $μ$m in diameter is found in the organic Mott system $κ$-[($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.

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T. Sasaki, N. Yoneyama, N. Kobayashi, Y. Ikemoto, H. Kimura. 2004-02-05. Imaging phase separation near the Mott boundary in the correlated organic superconductors $κ$-(BEDT-TTF)$_{2}$X. https://doi.org/10.1103/physrevlett.92.227001

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