Conditions of Electronic Structure to Obtain Large Dimensionless Figure of Merit for Developing Practical Thermoelectric Materials

Abstract

The highest value of the dimensionless figure of merit ZT obtainable from a given electronic structure was quantitatively estimated from the linear response theory by considering the normalized spectral conductivity. It was found, by calculating ZT from the possible electronic structures, that the bulk materials with the electronic structure consisting of two bands overlapping together near the Fermi level have potential to possess a large ZT-value exceeding unity.