Anisotropic magnetic and magnetotransport properties in morphologically distinct Nd0.6Sr0.4MnO3 thin films

Abstract

Abstract We investigate the magnetic and magnetotransport properties of nanostructured Nd0.6Sr0.4MnO3 (NSMO) thin films grown on (100) oriented SrTiO3 (STO) substrates. The thin films of 100 nm thickness fabricated using the pulsed laser deposition technique possess two distinct surface morphologies—granular and nano-rod type. The morphological change present in the system significantly affects the magnetic and magnetotransport properties of the thin films. Magnetization measurements revealed that the films with rod-type morphology exhibit improved in-plane magnetic anisotropy. The colossal magnetoresistance (∆R/R(H = 0)) of the granular sample is ∼91 %, and the rod morphology sample is ∼97 % at 3 T magnetic field. Additionally, magnetotransport studies revealed that the granular thin films display a characteristic butterfly-shaped low-field magneto-resistive (LFMR) behavior with the value of LFMR of up to ∼10 %. Furthermore, it is observed that the thin film’s morphology has a significant effect on the anisotropic magnetoresistance ratio (AMR). Thin films with rod-type morphology show an enhanced AMR of ∼30 % around its metal-insulator transition temperature. Such morphology-dependent tunability in magnetoresistance properties over a wide temperature range is potentially interesting for developing oxide-based sensors and devices.