Electron Spin Resonance in Ti-Doped VO₂

Abstract

The behavior of carriers trapped around doped Ti ions in VO₂ is investigated by means of the electron spin resonance in a temperature range between liquid nitrogen and room temperature. The line shapes are examined for different concentration of Ti. At lower concentration well resolved hyperfine lines are observed and a broad background line is superposed to them. With increasing impurity concentration, however, the single broad line grows up and the hfs lines diminish. At higher concentration only a single broad line of the Lorentz type is observed. The temperature dependences of the linewidth and the intensity for the hfs and broad lines are measured. The width of the broad line which does not vary at low temperature starts to increase at a temperature above which the intensity deviates from the Curie law. The motion of carriers localized around Ti impurity centers is discussed from these results.