Superconductivity and metal to insulator transition in homogeneously disordered molybdenum thin films

Abstract

Disorder driven metal to insulator transition is reported in three dimensional thin films of molybdenum, deposited at room temperature using DC magnetron sputtering at different argon pressures. The disorder is tuned using deposition pressure as the sole parameter. A variation of particle sizes, room temperature resistivity and superconducting transition has been studied as a function of deposition pressure. The disordered molybdenum thin films are found to have large carrier concentration but very low mobility. Hall and conductivity measurements have been used to understand the effect of disorder on the carrier density and mobilities. Ioffe-Regel parameter is shown to correlate with the continuous metal-insulator transition in our samples.