Room-temperature thousandfold magnetoresistance change in MnSb granular films: Magnetoresistive switch effect

A huge positive magnetoresistance effect has been discovered in MnSb granular films. Granular film consisting of nanoscale MnSb dots that are grown on a sulfur-passivated GaAs (001) substrate by molecular-beam epitaxy, then covered with an Sb thin layer, exhibits magnetic-field-sensitive current–voltage characteristics. When a constant voltage, above the threshold value, is applied to the film, more than 1000% change in the current, which we term magnetoresistive switch, is driven by the magnetoresistance effect under a relatively low magnetic field (less than 0.5 T) at room temperature.