Broadband Phase-change Metagrating Design for Efficient Active Reflection Steering

• Published in: Current optics and photonics Vol. 5; no. 2; pp. 134 - 140
• Main Author: Kim, Sun-Je
• Format: Journal Article
• Language: Korean
• Published: 2021
• Subjects: Diffraction; Grating; Subwavelength structures; Metasurface; Spatial light modulator
• ISSN: 2508-7266

In this paper, I introduce a novel design method of a high performance nanophotonic beam deflector providing broadband operation, large active tunability, and signal efficiency, simultaneously. By combining thermo-optically tunable vanadium dioxide nano-ridges and a metallic mirror, reconfigurable local optical phase of reflected diffraction beams can be engineered in a desired manner over broad bandwidth. The active metagrating deflectors are systematically designed for tunable deflection of reflection beams according to the thermal phase-change of vanadium dioxide nano-ridges. Moreover, by multiplexing the phase-change supercells, a robust design of actively tunable beam splitter is also verified numerically. It is expected that the proposed intuitive and simple design method would contribute to development of next-generation optical interconnects and spatial light modulators with high performances. The author also envisions that this study would be fruitful for modern holographic displays and three-dimensional depth sensing technologies.