Enhancing low-field magnetoresistance of La_0.67Ca_0.33MnO₃ films deposited on anodized aluminium-oxide membranes

In this paper we report a new method to fabricate nanostructured films. La_0.67Ca_0.33MnO₃ (LCMO) nanostructured films have been fabricated by using pulsed electron beam deposition (PED) on anodized aluminium oxide (AAO) membranes. The magnetic and electronic transport properties are investigated by using the Quantum Design physics properties measurement system (PPMS) and magnetic properties measurement system (MPMS). The resistance peak temperature (T_p) is about 85\,K and the Curie temperature (T_c is about 250 K for the LCMO film on an AAO membrane with a pore diameter of 20\,nm. Large magnetoresistance ratio (MR) is observed near T_p. The MR is as high as 85% under 1 T magnetic field. The great enhancement of MR at low magnetic fields could be attributed to the lattice distortion and the grain boundary that are induced by the nanopores on the AAO membrane.