Electronic Properties Close to Dirac Cone in Two-Dimensional Organic Conductor $\alpha$-(BEDT-TTF)${}_2$I${}_3$

Shinya Katayama, Akito Kobayashi, Yoshikazu Suzumura

A zero-gap state (ZGS) has been found in a bulk system of two-dimensional organic conductor, $\alpha$-(BEDT-TTF)${}_2$I${}_3$ salt which consists of four sites of donor molecules in a unit…