Thermal Expansion of n-Type Doped Bi2Te2.88Se0.12 and p-Type Doped Bi0.52Sb1.48Te3 Solid Solutions from −60°C to +60°C

Abstract

An automated dilatometric system was developed to measure the thermal expansion of solid materials from À60°C to +400°C. This system was then applied to measure the linear thermal expansions of n-type doped Bi 2 Te 2.88 Se 0.12 and p-type doped Bi 0.52 Sb 1.48 Te 3 solid solutions along the a-axis from À60°C to +60°C. The experiments were performed using a vertical ''tube/ push rod'' dilatometer under constant-temperature conditions. The initial alloys were synthesized from Bi, Te, and Se or Sb (each at 99.999 mass% purity) in stoichiometric ratios. The method based on the correlation between the thermal expansion and the heat capacity was proposed to calculate the axial expansion coefficients along the c-axis.