  A coherent XY machine (CXYM) is a physical spin simulator that can simulate
the XY model by mapping XY spins onto the continuous phases of non-degenerate
optical parametric oscillators (NOPOs). Here, we demonstrated a large-scale
CXYM with >47,000 spins by generating 10-GHz-clock time-multiplexed NOPO pulses
via four-wave mixing in a highly nonlinear fiber inside a fiber ring cavity. By
implementing a unidirectional coupling from the i-th pulse to the (i+1)-th
pulse with a variable 1-pulse delay planar lightwave circuit interferometer, we
successfully controlled the effective temperature of a one-dimensional XY spin
network within two orders of magnitude.
