I have read Fujitsu's white paper for a brief introduction to their device: http://marketing.us.fujitsu.com/rs/407-MTR-501/images/quantum-inspired-computing.pdf As far as I know, Fujitsu's hardware is not quantum-mechanical. They call it a digital annealer inspired by quantum phenomenon. I'm curious about what it actually is, and what kind of algorithm it runs. Is it a classical computer or some specialized annealing device? If the former, what kind of annealing algorithm does it use? As for the latter, I'm not sure whether that kind of device actually exists. (Quantum annealers like the ones D-wave has belongs to this category, but Fujitsu doesn't have those.)
The first google search gives the research paper by Aramon et al. According to the article:
The Fujitsu Digital Annealer is designed to solve fully connected quadratic unconstrained binary optimization (QUBO) problems. It is implemented on application-specific CMOS hardware and currently solves problems of up to 1,024 variables. The Digital Annealer's algorithm is currently based on simulated annealing; however, it differs from it in its utilization of an efficient parallel-trial scheme and a dynamic escape mechanism. In addition, the Digital Annealer exploits the massive parallelization that custom application-specific CMOS hardware allows.
So basically, it is specialized hardware that runs a variant of the simulated annealing algorithm.