Phase transitions and semiconductor-metal transition in V1−xGaxO2 Single Crystals

Abstract

The electrical, thermoelectric, magnetic, and crystallographic properties of Ga-doped VO2 single crystals V1−xGaxO2 (0 ≦ x ≦ 0.013) are investigated. By Ga-doping the transition temperature of the semiconductor-metal transition of VO2 is elevated and the resistivity discontinuity is little increased. The T–x-phase diagram containing the phases M1, T, M2, and R is indicated. The phase transition T-M2 is a semiconductor-semiconductor transition with discontinuities in the properties investigated. By Ga-doping portions of anisotropic p-conduction arise. Without falsifying by paramagnetic ions the magnetism of linear Heisenberg chains with antiferromagnetic interaction may be seen in the M2 phase.