Scalable Ising Computer Based on Ultra-Fast Field-Free Spin Orbit Torque Stochastic Device with Extreme 1-Bit Quantization

The Ising computer has great potential to solve complicated combinatorial optimization problems which beyond the capability of conventional computer unless the two major obstacles of easy-control high-speed low-power individual P-Bit and scalable large P-Bit array are overcame. In this work, an ultra-fast field-free P-Bit tunable by Spin Orbit Torque (SOT) Effect is proposed and carefully verified by throughout experimental measurement. Further, for the first time, an extreme 1-Bit quantization method against device variation is proposed for the hardware implementation of Ising computer with large P-Bit array. A novel Pareto front analysis methodology of Kullback-Leibler Divergence (KLD) is proposed to provide the practical and convenient criteria for the scalability judgement to large P-Bit array.