Spin-Transfer-Torque Driven Magneto-Logic Gates Using Nano Spin-Valve Pillars

Abstract

We propose model magneto-logic NOR and NAND gates using a spin valve pillar, wherein the logical operation is induced by spin-polarized currents which also form the logical inputs. The operation is facilitated by the simultaneous presence of a constant controlling magnetic field. The same spin-valve assembly can also be used as a magnetic memory unit. We identify regions in the parameter space of the system where the logical operations can be effectively performed. The proposed gates retain the non-volatility of a magnetic random access memory (MRAM). We verify the functioning of the gate by numerically simulating its dynamics, governed by the appropriate Landau-Lifshitz-Gilbert equation with the spin-transfer torque term. The flipping time for the logical states is estimated to be within nano seconds. * murugesh@iist.ac.in 2

Extraordinary Hall effect based magnetic logic applications

“…This comparator device is one example among the many proposed logic devices based on magnetic spin valves (SVs) or MTJs. [1][2][3][4] SVs and MTJs are already widely used in industry as sensors 5,6 and their properties will continue to be improved since they are considered for the next generation of spintronic applications, e.g., spin-transfer torque magnetic random access memory (STT-MRAM) [7][8][9] and spin-transfer nano-oscillators (STNOs). [10][11][12] However, those spintronic devices are rather complex from the material and the micro and nanoelectronic process point of view which may affect cost and reproducibility.…”