Low-temperature thermal conductivity of tellurium-doped bismuth

Phonon thermal conductivities κ"2"2 (∇T || C"1) and κ"3"3 (∇T || C"3) of tellurium-doped bismuth with an electron concentration in the range 1.8 × 10¹⁹ ≤ n(L) ≤ 1.4 × 10²⁰ cm(-3) were studied in the temperature interval 2 < T < 300 K. The temperature dependence of the phonon thermal conductivity obtained on doped bismuth samples of both orientations exhibits two maxima, one at a low temperature and the other at a high temperature. The effect of various phonon relaxation mechanisms on the dependence of both phonon thermal conductivity maxima on temperature, impurity concentration, and electron density is studied.