Current induced magnetization switching in an antiperovskite nitride exchange-coupled bilayer

Abstract

Recently, current-induced spin transfer torque is attracting interest because it affects not only a FM but also an AFM [1, 2]. Furthermore, the critical current for AFM switching is more than 10−2 times smaller than typical value for a FM [1]. Therefore, FM/AFM bilayers containing half-metallic FMs are desirable for studying current-induced magnetization switching and spin torque in AFM materials. Up to now, we focused on antiperovskite nitride [3, 4] because there are many combinations of elements that form the antiperovskite nitride such a AFM materials and half-metallic FM. Anti-perovskite FM nitride Co 3 FeN is predicted that it has high negative spin polarization [3, 4]. Anti-perovskite AFM nitride Mn 3 GaN exhibits many interesting properties, such as piezomagnetic [5]. For Mn 3 GaN/Co 3 FeN bilayer, we expect application to the new devices controlling magnetic moments of Mn 3 GaN by spin transfer torque. In this study, we investigated current-induced magnetization switching in Mn 3 GaN/Co 3 FeN epitaxial exchange-coupled bilayers by employing AMR effect. We shall discuss spin transfer torque in antiferromagnetic Mn 3 GaN.