Magnetic point contact in ferromagnetic semiconductor (Ga,Mn)As

Abstract

We show that narrow constrictions, a few hundred nanometers wide, in ferromagnetic semiconductor (Ga,Mn)As layer exhibit large spin-related magnetoresistance. Moreover, we demonstrate that application of oxygen-ions implantation, instead of chemical etching, is much better method of tailoring nanometer-size circuits in (Ga,Mn)As suitable for future spin electronics.