Nonlinear processing with only linear optics (nPOLO)

As artificial intelligence (AI) use grows, the demand for computing resources has increased dramatically. Server costs are significant and highlight the need for more energy-efficient and cost-effective computing platforms for AI applications and future growth. One potential solution is optical hardware. Optical computing hardware has several advantages, such as high bandwidth parallelism and energy efficiency. However, one major limitation is the implementation of nonlinear calculations in the optical domain. We will discuss an approach that achieves the equivalent of optical nonlinearity vastly more effectively than current approaches. The essence of the technique relies on multiple linear scattering off data encoded onto a spatial light modulator (SLM) that uses low optical power to effectively synthesise a nonlinear operation. By exploiting this relationship, arbitrary nonlinear transformations are programmed digitally, and light effectively performs an all-optical computation without requiring electronic switching or high peak power to achieve non-linearity.