A dimensionless Hamiltonian of an N-spin Ising model without an external magnetic field (Fig. 1a) is given by Figure 1: Ising model and set-up for generating artificial Ising spins based on DOPOs.

Quantum annealers are devices that physically implement a quantum system called the 'Ising model' to solve combinatorial optimization problems. However, the coefficients of the Ising model often ...