Reduced electric dead layer in tensile strained La2/3Ca1/3MnO3 ultrathin films

Abstract

The formation of self-assembly network of antidots has been accomplished in La2/3Ca1/3MnO3 ultrathin films. Grazing incidence X-ray diffraction measurements show that the strain is maintained throughout the film until the surface. With decreasing thickness, both magnetization and paramagnetic-to-ferromagnetic transition temperature decrease due to enhanced structural inhomogeneities at surface/interface. The surface/interface disorder also leads to the transition from metal to localized character that can be well described by a variable range hopping model at low temperatures. An electric dead layer less than 6nm has been realized on SrTiO3 substrate, which has a positive effect on the performance of La2/3Ca1/3MnO3-based magnetic tunnel junction applications.