Epitaxial <b> <i>γ</i> </b> -CoMn films for antiferromagnetic spintronics

Abstract

γ -phase alloy materials are of great interest for spintronics due to their antiferromagnetism depending on the interatomic separation. γ-CoMn, as a typical antiferromagnetic 3d transition metal alloy, has been the subject of numerous studies regarding its underlying antiferromagnetism origin determined by the competition between interatomic exchange interactions and interatomic election motion. However, the difficulty of growing single-crystalline γ-CoMn films on insulating substrates has prevented from their magnetoelectronic transport investigations and further applications. Here, we report the epitaxial growth, structural characterization, and magnetic and transport properties of γ-Co40Mn60 films on Cu buffered Si(111) substrate. Reflection high-energy electron diffraction and high-resolution x-ray diffractometry have manifested the successful epitaxial growth of high-quality γ-Co40Mn60 films. The antiferromagnetism resistivity minimum with temperature and Hall resistance deviation from magnetization indicate γ-CoMn is a promising antiferromagnetic material for spintronic investigations.