Low-field magnetoresistance in La2/3Sr1/3MnO3 granular composites by a sol–gel coating process

The La2/3Sr1/3MnO3 granular composites have been prepared by a sol–gel coating process, in which the transport and magnetic properties have been systematically measured. It has been found that the low-field MR is enhanced owing to tunneling between the large and small La2/3Sr1/3MnO3 grains. Furthermore, the hysteretic MR behavior can be attributed to the different magnetization processes of the large and small ferromagnetic grains.