Domain wall magnetoresistance in a nanopatterned La(2/3)Sr(1/3)MnO3 track

TL;DR

This study measures the resistance contribution of magnetic domain walls in nanopatterned La(2/3)Sr(1/3)MnO3 tracks, revealing a large DW resistance-area product and its dependence on current and temperature.

Contribution

It provides the first detailed measurement of domain wall resistance in manganite films and shows how it varies with current and temperature, highlighting differences from 3d ferromagnets.

Findings

DW resistance-area product is ~2.5×10^(-13) Ohm/m^2 at low temperature

DW resistance increases with injected current, indicating spin-transfer effects

DW resistance vanishes around 225K, linked to film anisotropy

Abstract

We have measured the contribution of magnetic domain walls (DWs) to the electric resistance in epitaxial manganite films patterned by electron-beam lithography into a track containing a set of notches. We find a DW resistance-area (RA) product of ~2.5 10^(-13) Ohm/m^2 at low temperature and bias, which is several orders of magnitude larger than the values reported for 3d ferromagnets. However, the current-voltage characteristics are highly linear which indicates that the DWs are not phase separated but metallic. The DWRA is found to increase upon increasing the injected current, presumably reflecting some deformation of the wall by spin-transfer. When increasing temperature, the DWRA vanishes at ~225K which is likely related to the temperature dependence of the film anisotropy.