Giant quantum oscillations of the longitudinal magnetothermopower at the electron topological transition induced by stretch of quantum wires of bismuth doped with Te

摘要

Thermoelectric and magneto-thermoelectric properties of quantum wires of bismuth doped with Te were investigated at electron topological transitions (ETT) induced by stretch in the temperature interval 4.2-300 K and magnetic fields up to 14T. Single Bi, Bi wires were obtained by the liquid phase casting by the Ulitovsky method. They were single crystals of strictly cylindrical form in a glass cover with orientation <1011> along the wire axis. In thin wires of Bi doped with Te a number of anomalies were found out at ETT, of the type of formation of new Fermi surface cavity (T-hole) induced by extension. The giant oscillations of the thermopower in magnetic field and singularities in deformation curves of thermopower and resistance may be referred to these anomalies. In general they give evidence that the intervally scattering of carriers plays the significant role in wires of Bi and Te-doped Bi in the low temperature range.