Large-scale artificial spin network based on time-multiplexed degenerate optical parametric oscillators for coherent Ising machine
Hiroki Takesue, Takahiro Inagaki, Kensuke Inaba, Ryan Hamerly, Kyo Inoue, Y. Yamamoto · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 2017
We describe a large-scale degenerate optical parametric oscillator (DOPO) network for a coherent Ising machine that solves combinatorial optimization problems. By pumping a fiber-based phase-sensitive amplifier placed in a 1-km fiber cavity at a 2-GHz repetition frequency, we generated more than 10,000 DOPOs multiplexed in the time domain. We confirmed that the DOPO phases were discretized to {0, π} indicating that they could be used as stable artificial spins. We also implemented a one-dimensional Ising model by optically coupling adjacent DOPOs, and confirmed that the DOPOs well simulated the behavior of low-temperature spins.