Electronic effects on the elastic constants of n-type gallium antimonide

Abstract

The second-order elastic stiffness constants of three n-type Te-doped GaSb single crystals were measured by the ultrasonic pulse interference method at 25 °C. Carrier concentrations of the samples are: 1.9×1017, 7.7×1017, and 1.2×1018 per cm3. The largest electronic effect was found in C44: a decrease of 0.32% for the highest doped sample compared with the lowest doped sample. The experimental results were interpreted in terms of Keyes’ theory, which is based on the consideration of electronic free energy. The shear deformation potential Ξ(111)u of the (111) band was found to be 16.5±1.8 eV. The longitudinal deformation potential Ξ(111)d was also estimated.

Mechanical behaviour of thermoelectric materials – a perspective

“…Another aspect of interest is the effect of carrier concentration on the elastic constants. The doping-induced strain alters the populations of the electronic states, which changes the total electronic energy of the material and subsequently its total elastic energy [98,99]. Experimentally, a 6–8% change in the elastic moduli is noticed due to changes in the carrier concentration [95,99].…”