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First-Principles Study of Electronic Structure in $α$-(BEDT-TTF)$_2$I$_3$ at Ambient Pressure and with Uniaxial Strain

Hiori Kino·Tsuyoshi Miyazaki
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Abstract

Within the framework of the density functional theory, we calculate the electronic structure of $α$-(BEDT-TTF)$_2$I$_3$ at 8K 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.

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Hiori Kino, Tsuyoshi Miyazaki. 2006-01-04. First-Principles Study of Electronic Structure in $α$-(BEDT-TTF)$_2$I$_3$ at Ambient Pressure and with Uniaxial Strain. https://doi.org/10.1143/jpsj.75.034704

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