The magneto-Peltier-Seebeck figure of merit of Te-doped Bi₉₅Sb₅ at 80 K

The Seebeck coefficient, thermal conductivity and electrical conductivity of crystals of Bi₉₅Sb₅ doped with various amounts of Te have been measured at 80 K, using samples that were oriented so as to yield the highest thermoelectric figure of merit. A dimensionless figure of merit of 0·58 has been observed for a crystal doped with nominally 0·002 at.% Te in a magnetic field of 0·4 T, this being significantly higher than the best value that was found for an intrinsic crystal.

From the change of thermal conductivity with magnetic field it has been possible to estimate a value of 2.8 W m⁻¹ K⁻¹ for the lattice conductivity. A rather low Lorenz number is attributed to inelastic scattering of the electrons.