Physical reservoir computing based on spin torque oscillator with forced synchronization

Abstract

We investigated physical reservoir computing (RC) using a vortex-type spin torque oscillator (STO) as a resource of nonlinear dynamics, which is essential for processing information in time-series data. Forced synchronization was used to suppress the thermal fluctuation of the oscillation trajectory of the STO. We examined the memory property of the STO dynamics, called short-term memory (STM), by using a virtual node technique. The STM capacity increased about twofold compared with that obtained without forced synchronization. The performance index for the nonlinear transformation of the STO also increased; it was evaluated in a parity-check task. The results prove that the synchronized STO has great potential for physical RC based on nanotechnology.