Investigation of the gapless state in CuFeTe₂

Abstract

The CuFeTe2 ternary compound with a layered crystalline structure has been studied. The compound is paramagnetic in the temperature range 1-200 K. Investigation of the mu (T) temperature dependence demonstrates the ferron character of the carrier transport with the Mott diffusional mechanism. The obtained power dependences n(T), R(T) and sigma (T) allow the authors to conclude that CuFeTe2 belongs to the gapless semiconductors. The temperature behaviour of n(T), R(T) and sigma (T) can be explained by examining features from the electron spectrum of CuFeTe2 under conditions where the character of the carrier transport is dose to the zone type and the general character of the spectrum is determined by the symmetry group and by the type of irreducible representation of the group.