Domain wall pinning and domain wall resistivity in notched La 0.7 Sr 0.3 MnO 3 nanostructures
Year: 2025
Type: article
Abstract: Creation and manipulation of magnetic domain walls (DWs) are a core subject of research in developing prototype devices for spintronic applications. DWs can be created artificially and moved by applying either a magnetic field or an electric current, as has been extensively investigated. Here, we study the DW pinning and depinning in half-metallic ferromagnetic La 0.7 Sr 0.3 MnO 3 nanostructures with a notch that is about 90% of the width of the wire. By measuring the magnetoresistance of the notched wires while sweeping the magnetic field, we unambiguously observe DW pinning and depinning from 10 to 300 K. Analysis of the temperature dependence reveals that both Δ R (the DW resistance) and Δ R / R 0 ( R 0 is the resistance at zero field) are proportional to the temperature. The DW resistivity is calculated to be of the order of 10 − 17 Ω m 2 at 10 K and 10 − 15 Ω m 2 at 300 K. The latter value agrees with the reported intrinsic DW resistivity in films. In addition, we find approximately constant Δ R and Δ R / R 0 for widths from 5 down to 1.8 µ m and a pronounced increase in both quantities when the width goes down to 755 nm. With the extracted magnetocrystalline anisotropy parameters from the measurements of the remanent magnetization and the magnetic torque as function of angle of the magnetic field with respect to the substrate normal, we further perform micromagnetic simulations and obtain results consistent with the experimental data. Our work may promote designing relevant prototypes and may constitute a platform to explore the effect of spin torque transfer on DWs.
Source: Physical Review Materials
DOI: 10.1103/np4m-j4b7
Language: English
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: hybrid
OpenAlex ID: W4413640997