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Electric Conductivity of the Zero-gap Semiconducting State in Alpha-(BEDT-TTF)2I3 Salt

Shinya Katayama·Akito Kobayashi·Yoshikazu Suzumura
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Abstract

The electric conductivity which reveals the zero gap semiconducting (ZGS) state has been investigated as the function of temperature $T$ and life time $τ$ in order to understand the ZGS state in quarter-filled $α$-(BEDT-TTF)$_2$I$_3$ salt with four sites in the unit cell. By treating $τ$ as a parameter and making use of the one-loop approximation, it is found that the conductivity is proportional to $T$ and $τ$ for $k_B\gg\hbar/τ$ and independent of $T$ and $τ$ for $k_B T\ll\hbar/τ$. Further the conductivity being independent of $T$ in the ZGS state is examined in terms of Born approximation for the impurity cattering.

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Shinya Katayama, Akito Kobayashi, Yoshikazu Suzumura. 2006-01-04. Electric Conductivity of the Zero-gap Semiconducting State in Alpha-(BEDT-TTF)2I3 Salt. https://doi.org/10.1143/jpsj.75.023708

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