Large-scale ising machine based on spatial light modulation

Physical systems that evolve according to an Ising Hamiltonian are currently attracting an enormous research interest as novel computing architectures for solving optimization problems that cannot be tackled efficiently on large scales by conventional hardware. In particular, it has been recently demonstrated that photonic platforms such as coherent Ising machines [1,2] and nanophotonic circuits [3] can find the ground state of a classical system of spins with programmable interactions. However, all the proposed optical machines either involve a limited number of spins or fail to properly solve large-scale systems. Although spatial optical waves can present spin-glass dynamics [4] and matrix operations can also be performed by spatially shaped fields [5], the use of spatial optical modulation to solve Ising spin models has remained unexplored. Here, we exploit the spatial degree of freedom of light to realize an optical Ising machine with an unprecedented number of interacting spins [6].