Structural and transport properties for Al- and Fe-doping La0.67Ca0.33MnO3 perovskite manganese

The effects of Al and Fe ion doping in Mn sites was studied for the colossal La0.67Ca0.33MnO3 magnetoresistance material. It was found that when Fe-doping amount x increases, the crystal cell structure has no obvious change, but the crystal cell volume decrease monotonically for Al-doping. Both resistances increase rapidly and the insulator-metal transition temperature moves to lower temperature and decreases linearly with Al-doping. The area for Al-doping is broader than Fe. At small amount of AT-doping, the resistance satisfy metal transport property when T < T-IM. The characteristic of the transport behaviour for Al- and Fe-doping can be explained by terminating the double exchange channel of Mn3+-O2--Mn4+.