Thermal conductivity of liquid semiconductor thallium-tellurium solutions

Abstract

A study has been made of the thermal conductivity K of liquid thallium-tellurium solutions in a composition range where they have semiconductor behaviour. The data are compared with conventional theories for electronic structure and transport, making use of existing information about the electrical properties of these solutions. At a composition which is n-type, but not far from intrinsic, a rapid rise in the experimental value of K with increasing T can be ascribed, at least in part, to ambipolar diffusion. At p-type compositions, the thermal conductivity is found to vary linearly with the product of the electrical conductivity and the absolute temperature over considerable ranges of temperature and concentration, in accordance with the Wiedemann-Franz law. However, the slope differs appreciably from the value for the Wiedemann-Franz ratio derived from conventional transport theory. Some of the possible reasons for the observed behaviour are discussed.