Thermal Expansion 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 from -60 deg C to +60 deg C

摘要

An automated dilatometric system was developed to measure the thermal expansion of solid materials from -60 deg C to +400 deg 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 -60 deg C to +60 deg 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(percent) 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.