GaMnN epitaxial films with high magnetization

TL;DR

This paper reports the successful fabrication of GaMnN epitaxial films with high Mn concentration, demonstrating homogeneous Mn distribution and significant ferromagnetism, advancing potential spintronic applications.

Contribution

It presents a method to grow high-quality GaMnN films with uniform Mn distribution and high magnetization, which was not previously achieved.

Findings

Homogeneous Mn distribution confirmed by spectroscopy and microscopy.

Linear increase of lattice parameter with Mn concentration.

Saturation magnetization up to 150 emu/cm^3.

Abstract

We report on the fabrication of pseudomorphic wurtzite GaMnN grown on GaN with Mn concentrations up to 10% using molecular beam epitaxy. According to Rutherford backscattering the Mn ions are mainly at the Ga-substitutional positions, and they are homogeneously distributed according to depth-resolved Auger-electron spectroscopy and secondary-ion mass-spectroscopy measurements. A random Mn distribution is indicated by transmission electron microscopy, no Mn-rich clusters are present for optimized growth conditions. A linear increase of the c-lattice parameter with increasing Mn concentration is found using x-ray diffraction. The ferromagnetic behavior is confirmed by superconducting quantum-interference measurements showing saturation magnetizations of up to 150 emu/cm^3.