High-Fidelity Spatial Photonic Ising Machines via Precise Wavefront Shaping

Abstract: Ising machines are emerging as a powerful physical alternative to digital processors for solving combinatorial optimization problems. Among them, spatial photonic Ising machines (SPIMs) offer compact, room-temperature hardware with inherently parallel, energy efficient, single-shot optical evaluation of the Ising Hamiltonian. However, scalability has been fundamentally limited by optical aberrations and non-uniform illumination, which corrupt phase-based spin encoding and distort coupling representation, forcing operation to a restricted spatial light modulator (SLM) region. Here we introduce a high-precision full-aperture calibration scheme that overcomes these constraints. By implementing wavefront retrieval and correction with < λ/40 accuracy, we restore faithful phase encoding across the entire SLM area. Furthermore, we introduce a novel interaction-normalization method, which compensates for amplitude curvature and enables uniform coupling representation. Together, these advances establish a high-fidelity, full-area SPIM architecture that unlocks true scalability and enables larger and more reliable photonic Ising computations.