Low field anisotropic colossal magnetoresistance in $Sm_{0.53} Sr_{0.47} Mn O_3$ thin films

TL;DR

This study reports on the highly anisotropic colossal magnetoresistance in thin films of Sm0.53Sr0.47MnO3, showing significant potential for magnetic sensor applications due to its large directional dependence of MR.

Contribution

It demonstrates the observation of colossal anisotropic magnetoresistance in Sm0.53Sr0.47MnO3 thin films, with detailed analysis of magnetic anisotropy and domain effects.

Findings

Out-of-plane anisotropic MR reaches 88% at 78 K and 3.6 kOe.

Magnetization easy axis lies in the plane, hard axis along the normal.

Colossal anisotropy explained by magnetic anisotropies and domain motion.

Abstract

SSMO5347 thin films (thicknesses ~200 nm) were deposited by on-axis dc magnetron sputtering on the single crystal LSAT (001) substrates. These films are oriented along the out of plane c-direction. The ferromagnetic and insulator-metal transition occurs at 96 K and 91 K, respectively. The magnetization easy axis is observed to lie in the plane of the film while the magnetic hard axis is found to be along the normal to this. The magnetotransport of the SSMO films, which was measured as a function of angle (theta) between the magnetic field (H) and plane of the film, shows colossal anisotropy. Magnetoresistance (MR) decreases drastically as theta increases from 0 degree (H//easy axis) to 90 degree (H//hard axis). The out-of-plane anisotropic MR (AMR) is as high as 88 % at H=3.6 kOe and 78 K. The colossal anisotropy has been explained in terms of the magnetic anisotropies at play and the magnetic domain motion in applied magnetic field.