High-Fidelity Spatial Photonic Ising Machines via Precise Wavefront Shaping

TL;DR

This paper presents a high-precision calibration and normalization method for spatial photonic Ising machines, significantly improving their scalability and reliability in solving complex optimization problems.

Contribution

The authors develop a wavefront correction and interaction-normalization technique that enables full-area, high-fidelity operation of spatial photonic Ising machines, overcoming previous limitations.

Findings

Achieved wavefront retrieval with < λ/40 accuracy across the entire SLM.

Restored faithful phase encoding over the full SLM area.

Enabled larger, more reliable photonic Ising computations.

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 < {\lambda}/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.