Techniques to modulate spin orbit spin transfer torques for magnetization manipulation

Abstract

In one embodiment, a SO-STT device has a non-symmetric device geometry. The device may be fabricated to have a non-symmetric magnetic pattern by tilting a shaped magnetic pattern (e.g., an ellipse, diamond, rectangle, etc. shaped magnetic pattern) such that the pattern's main (long and short) axes are tilted with respected to an in-plane current direction. Alternatively, the non-symmetric device geometry may be produced by locating the magnetic pattern away from the center of a current injection line. The non-symmetric may permit switching absent application of an external magnetic field. A SO-STT device with non-symmetric device geometry, or another type of SO-STT device, may further integrate an additional semiconductor, insulator or metal layer into the device's multilayer stack. By integrating the additional semiconductor, insulator or metal layer, a significant reduction of SO-STT switching current density may be achieved. Depending on the embodiment, the additional semiconductor, insulator or metal layer may be disposed adjacent to the FM layer, or within the FM layer, among other possibilities.