A 64-Spin All-to-All CMOS Ising Machine with Landscape Perturbation Achieving 2.28 nJ/Edge-Bit Energy-to-Solution

Abstract: A 64-spin all-to-all current-mode coupling Ising machine is implemented in 65 nm CMOS. The design supports 31 coefficient levels in 0.943 mm2 and achieves Energy-to-Solution (ETS) of 2.28 nJ/edge-bit. Continuous programming refresh not only mitigates leakage but also provides a mechanism for deterministic energy landscape perturbation, which consistently improves solution quality with higher success rate compared to operation without landscape perturbation.