Real Space Imaging of the Metal-Insulator Phase Separation of Micrometer Scale in the Highly Correlated Organic Conductors


   Real space imaging of the metal-insulator phase separation of micrometer scale has been successfully obtained in the highly correlated organic conductors κ-(BEDT-TTF)2Cu[N(CN)2]Br. The phase separation has consisted of the metal and the insulating domains of several 10 micrometer scale. This imaging has become possible by means of the scanning micro-region infrared spectroscopy (SMIS) method using high brilliance and directional infrared light from synchrotron radiation of SPring-8. The phase separation has been observed in the vicinity of the first order Mott transition of the κ-(BEDT-TTF)2Cu[N(CN)2]Br of which band width has been controlled by the partial substitution with the deuterated BEDT-TTF molecule. This work were performed in collaboration with Japan Synchrotron Radiation Institute. And the results were published in J. Phys. Soc. Jpn. 74, 2351 (2005), selected as Papers of Editor’s Choice, and appeared in some newspapers, Nikkan-Kogyo (August 12), Nikkei-Sangyo (August 15), and Kagaku-Shinbun (August 26).

Fig. Real space imaging of the metal-insulator phase separation