Electric and Thermoelectric Properties of Quantum Wires Based on Bismuth Semimetal and its Alloys.

The resistance R(T), the magnetoresistance R(H) and the Seebeck coefficient S(T) of thin mono-crystalline glass-coated wires of pure and doped by acceptor impurities (Sn) bismuth are studied. The measurements are carried out in the temperature range 4.2 - 300 K, and the magnetic fields up to 14 T. A significant dependence of the resistance R(T) and thermoemf S(T) on doping, sample diameter and surface state is revealed. By recrystallization, annealing and etching the samples a change in the surface scattering character of the charge carriers was achieved. The influence of the strong (up to 3-4%) elastic stretch on the band structure and kinetic coefficients of thin wires was studied. The thermoelectric figure of merit in doped bismuth wires is estimated, and possible ways of its increase in the temperature range 77 - 300 K are regarded.