Quantum corrections to low temperature electrical conductivity in Dy doped ZnO thin films

• Dy doped ZnO films were grown on sapphire substrate using pulsed laser deposition.
• All the Dy doped ZnO films show metal like behavior according to Mott's criteria.
• All the Dy doped ZnO thin films exhibited negative magneto-resistance.
• Observation of weak localization leading to Quantum corrections to conductivity

We have grown thin films of Dy doped ZnO (Dy:ZnO) on sapphire substrate using pulsed laser deposition with Dy concentration varying from 0.05 at.% to 1.8 at.%. These as grown Dy:ZnO thin films were characterized using low temperature four probe electrical measurements (in the range ~ 300 K to 4 K). All the Dy:ZnO thin films showed metal like behavior with a transition from positive to negative temperature coefficient of resistivity (TCR) and again to positive TCR with an increase of Dy concentration. This anomaly in conduction mechanism was investigated by considering quantum corrections to classical Boltzmann conductivity. All the Dy:ZnO thin films also exhibited negative magneto-resistance that supported for a significant contribution of weak localization in quantum corrections to conductivity.