Abstract

Spatial light modulators (SLMs) manipulate the polarization, amplitude and phase of incident light beams and are used in diverse applications as beam shaping and steering, digital holography and information processing [1]. Currently, most SLMs are based either on liquid crystal or on MEMS systems such as movable mirror arrays. The first ones have high resolution density and pixel size but low time response in the sub-ms range [2]. While the second ones have faster time responses in the order of hundredths of μs [3] and can be even faster by replacing conventional mirrors with high-contrast gratings (HCG) mirrors [4]. In the last years, other approaches based on metasurfaces and HCGs have been proposed as phase modulators by modulating the refractive index by exploiting the electro-optic or thermo-optic effects or by free-carrier injection [5, 6]. We propose a phase modulator also based on HCGs but exploiting the tunable optomechanical response capable of 2π shift variations and time responses in the order of hundreds of nanoseconds, limited by the mechanical resonance frequency.

© 2019 IEEE