High magnetoresistance in Bi_(0.91)Sb_(0.09) single crystals doped with Te and Sn

摘要

Investigations are presented of how donor and acceptor doping influence the magnetotransport in Bi_(0.91)Sb_(0.09) single crystals. Perfect and homogeneous Bi_(0.91)Sb_(0.09) single crystals with Te and Sn doping from 5 × 10~(-5) at. % to 10~(-3) at. % were grown by the Czochralski technique using a solid Sb feed. High carrier mobilities of up to 8.2 × 105 cm~2 V~(-1) s~(-1) at 77 K were achieved in these single crystals. In a magnetic field of LOT and at temperatures of less than 150 K, undoped and doped Bi_(0.91)Sb_(0.09) single crystals exhibited magnetoresistances higher than those of other materials. The influences of Te and Sn doping of Bi_(0.91)Sb_(0.09) single crystals, a feature of their band structure, and the changes of the carrier effective mass, density, and mobility in magnetic field on magnetoresistances and applicability of the Abrikosov quantum theory were studied. A high linear magnetoresistance of 5800% was reached in an Sn-doped (1.5 × 10~(-4) at. %) single crystal in a magnetic field of 1.15 T at 90 K. The present results suggest that the studied single crystals may be promising materials for magnetic sensors and multifunctional electromagnetic devices.