Effect of Ga$^{+}$ irradiation on magnetic and magnetotransport properties in (Ga,Mn)As epilayers

TL;DR

This study investigates how Ga$^{+}$ ion irradiation affects the magnetic and transport properties of (Ga,Mn)As epilayers, revealing reductions in conductivity and Curie temperature, along with enhanced magnetoresistance and altered magnetization behavior.

Contribution

It demonstrates the impact of focused ion beam irradiation on magnetic and transport properties of (Ga,Mn)As, providing insights into defect-induced modifications.

Findings

Reduced conductivity and Curie temperature after irradiation

Enhanced negative magnetoresistance at 4 K

Decreased hole carrier concentration observed in Raman spectra

Abstract

We report on the magnetic and magnetotransport properties of ferromagnetic semiconductor (Ga,Mn)As modified by Ga$^{+}$ ion irradiation using focused ion beam. A marked reduction in the conductivity and the Curie temperature is induced after the irradiation. Furthermore, an enhanced negative magnetoresistance (MR) and a change in the magnetization reversal process are also demonstrated at 4 K. Raman scattering spectra indicate a decrease in the concentration of hole carriers after the irradiation, and a possible origin of the change in the magnetic properties is discussed.