Topography and magnetoresistance in Nd0.6Sr0.4MnO films

The highly textured Nd0.6Sr0.4MnO3 thin films with different thickness t we re obtained. The maximum magnetoresistance (MR) ratio. defined as [R(0) - R (1.5 T)]/R(0) at the insulating- to metallic-phase transition temperature, was found to increase with decreasing t. reaching a value of 75% for t = 50 0 A. However, when t was further decreased down to 100 A, the MR ratio was not significantly affected. In conjunction with our topographic results, we have attributed the saturation of MR ratio to the achieving of an optimize d interface strain. (C) 2001 Elsevier Science B.V. All rights reserved.