Giant magnetoresistance in transition-metal-doped ZnO films

Magnetic and transport properties were investigated in Zn0.94Mn0.03Co0.03O thin films prepared by dual radio frequency magnetron sputtering technique. A negative magnetoresistance (MR=[rho(H)-rho(0)]/rho(0)) of -95% at 2 K and a positive MR of 48% at 10 K were established in the films. The anomalous magnetic and magnetic-related transport properties in transition-metal-doped ZnO films are discussed in terms of magnetic polarons. (c) 2006 American Institute of Physics.