First-principles study of electronic structure in α-(BEDT-TTF)2I3 at ambient pressure and with uniaxial strain

Within the framework of the density functional theory, we calculate the electronic structure of a(BEDT-TTF)(2)I-3 at 8 K and room temperature at ambient pressure and with uniaxial strain along the a- and b-axes. We confirm the existence of anisotropic Dirac cone dispersion near the chemical potential. We also extract the orthogonal tight-binding parameters to analyze physical properties. An investigation of the electronic Structure near the chemical potential clarifies that effects of uniaxial strain along the a-axis is different from that along the b-axis. The carrier densities show T-2 dependence at low temperatures, which may explain the experimental findings not only qualitatively but also quantitatively.