Phase-change spatial light modulators with amplitude-only control

Abstract

Current spatial light modulator (SLM) technology allows for the spatial control of the phase of light, but amplitude control is more limited. The realisation of a SLM that can efficiently modulate amplitude without altering the phase of the light would enable the development of devices that can perform full wavefront control. Here we discuss the design, fabrication and characterisation of such modulators using a phase-change material layer as the active component. These devices allow for the modulation of the amplitude of a reflected wave with near-zero change to its phase., providing a potential route to ultra-fast, solid-state wavefront control.