Takesue Hiroki, Inagaki Takahiro
Opt Lett. 2016 Sep 15;41(18):4273-6. doi: 10.1364/OL.41.004273.
A coherent Ising machine based on degenerate optical parametric oscillators (DOPOs) is drawing attention as a way to find a solution to the ground-state search problem of the Ising model. Here we report the generation of time-multiplexed DOPOs at a 10 GHz clock frequency. We successfully generated >50,000 DOPOs using dual-pump four-wave mixing in a highly nonlinear fiber that formed a 1 km cavity, and observed phase bifurcation of the DOPOs, which suggests that the DOPOs can be used as stable artificial spins. In addition, we demonstrated the generation of more than 1 million DOPOs by extending the cavity length to 21 km. We also confirmed that the binary numbers obtained from the DOPO phase-difference measurement passed the NIST random number test, which suggests that we can obtain unbiased artificial spins.
一种基于简并光学参量振荡器（DOPO）的相干伊辛机，作为解决伊辛模型基态搜索问题的一种方法正受到关注。在此，我们报告了在10 GHz时钟频率下时分复用DOPO的产生。我们利用双泵浦四波混频在形成1 km腔的高非线性光纤中成功产生了超过50,000个DOPO，并观察到DOPO的相位分岔，这表明DOPO可作为稳定的人工自旋。此外，我们通过将腔长度扩展到21 km演示了产生超过100万个DOPO。我们还证实，从DOPO相位差测量获得的二进制数通过了美国国家标准与技术研究院（NIST）随机数测试，这表明我们可以获得无偏的人工自旋。
