Vertical spin electronic device with large room temperature magnetoresistance

In this article we report the effect of double Schottky type barriers when a semiconductor layer is sandwiched between two ferromagnetic (FM) layers. A 15 ML of Co with 20 ML of Cr capping layers were deposited on As-adsorbed GaAs(100) substrate. The GaAs(100) substrate has following structure As-capping/GaAs(50 nm, n-type, 1018/cm)/Al0.3Ga0.3As(200 nm, n-type, 1018/cm)/GaAs(100). Optical lithography and selective chemical etching was performed on the thinned sample. A NiFe layer with 10 nm of Cr layer was thermally evaporated and lift-off was performed. As the MR becomes stable beyond the critical current at high fields, its rules put the possibility that the MR could be resulted from Lorentz force. On the contrary, the MR depends on bias current, and as we have a sandwich structure with a SM layer between two FM layers, we could not rule out the possibility that a contribution to this high room temperature MR could come from spin injection and detection through the FM layers.