We demonstrate a spin-wave-based time-multiplexed Ising Machine (SWIM), implemented using a 5 μm thick Yttrium Iron Garnet (YIG) film and off-the-shelf microwave components. The artificial Ising spins consist of 34--68 ns long 3.125 GHz spinwave RF pulses with their phase binarized using a phase-sensitive microwave amplifier. Thanks to the very low spinwave group velocity, the 7 mm long YIG waveguide can host an 8-spin MAX-CUT problem and solve it in less than 4 μs while consuming only 7 μJ. Using a real-time oscilloscope, we follow the temporal evolution of each spin as the SWIM minimizes its energy and find both uniform and domain-propagation-like switching of the spin state. The SWIM has the potential for substantial further miniaturization, scalability, speed, and reduced power consumption, and may become a versatile platform for commercially feasible optimization problem solvers with high performance.
@article{arxiv.2209.04291,
title = {A spinwave Ising machine},
author = {Artem Litvinenko and Roman Khymyn and Victor H. González and Ahmad A. Awad and Vasyl Tyberkevych and Andrei Slavin and Johan Åkerman},
journal= {arXiv preprint arXiv:2209.04291},
year = {2022}
}