Tunable Mie Resonances in the Visible Spectrum

TL;DR

This paper presents the design and experimental demonstration of tunable dielectric nanoantenna arrays with Mie resonances in the visible spectrum, using phase transitions in Sb2S3 nano-resonators for reversible color tuning.

Contribution

It introduces the first tunable dielectric nanoantenna arrays operating in the visible spectrum by exploiting phase change in Sb2S3 nanostructures.

Findings

Achieved reversible color tuning via phase transitions in Sb2S3 nano-resonators.

Demonstrated strong structural color in reflection mode in the amorphous state.

Enabled potential applications in color displays, holography, and LiDAR.

Abstract

Dielectric optical nanoantennas play an important role in color displays, metasurface holograms, and wavefront shaping applications. They usually exploit Mie resonances as supported on nanostructures with high refractive index, such as Si and TiO2. However, these resonances normally cannot be tuned. Although phase change materials, such as the germanium-antimony-tellurium alloys and post transition metal oxides, such as ITO, have been used to tune optical antennas in the near infrared spectrum, tunable dielectric antennae in the visible spectrum remain to be demonstrated. In this paper, we designed and experimentally demonstrated tunable dielectric nanoantenna arrays with Mie resonances in the visible spectrum, exploiting phase transitions in wide-bandgap Sb2S3 nano-resonators. In the amorphous state, Mie resonances in these Sb2S3 nanostructures give rise to a strong structural color in reflection mode. Thermal annealing induced crystallization and laser induced amorphization of the Sb2S3 resonators allow the color to be tuned reversibly. We believe these tunable Sb2S3 nanoantennae arrays will enable a wide variety of tunable nanophotonic applications, such as high-resolution color displays, holographic displays, and miniature LiDAR systems.