Broadband Mechanically Tunable Metasurface Reflectivity Modulator in the Visible Spectrum

Dorian Herle; Andrei Kiselev; Luis Guillermo Villanueva; Olivier J F Martin; Niels Quack

doi:10.1021/acsphotonics.3c00276

Broadband Mechanically Tunable Metasurface Reflectivity Modulator in the Visible Spectrum

ACS Photonics. 2023 May 31;10(6):1882-1889. doi: 10.1021/acsphotonics.3c00276. eCollection 2023 Jun 21.

Authors

Dorian Herle¹, Andrei Kiselev², Luis Guillermo Villanueva¹, Olivier J F Martin², Niels Quack^{1

3}

Affiliations

¹ Ecole Polytechnique Federale de Lausanne, Advanced Nano-Mechanical Systems Laboratory, EPFL STI IGM NEMS, Station 9, CH-1015 Lausanne, Switzerland.
² Ecole Polytechnique Federale de Lausanne, Nanophotonics and Metrology Laboratory, EPFL STI IMT NAM, Station 11, CH-1015 Lausanne, Switzerland.
³ School of Aerospace, Mechanical and Mechatronic Engineering, Mechanical Engineering (J07), University of Sydney, Blackwattle Creek Ln, Darlington, NSW 2008, Australia.

Abstract

Reflectivity modulation is a critical feature for applications in telecommunications, 3D imaging and printing, advanced laser machining, or portable displays. Tunable metasurfaces have recently emerged as a promising implementation for miniaturized and high-performance tunable optical components. Commonly, metasurface response tuning is achieved by electro-optical effects. In this work, we demonstrate reflectivity modulation based on a nanostructured, mechanically tunable, metasurface, consisting of an amorphous silicon nanopillar array and a suspended amorphous silicon membrane with integrated electrostatic actuators. With a membrane displacement of only 150 nm, we demonstrate reflectivity modulation by Mie resonance enhanced absorption in the pillar array, leading to a reflectivity contrast ratio of 1:3 over the spectral range from 400-530 nm. With fast, low-power electrostatic actuation and a broadband response in the visible spectrum, this mechanically tunable metasurface reflectivity modulator could enable high frame rate dynamic reflective displays.