Electrical Tuning of Phase Change Antennas and Metasurfaces

TL;DR

This paper demonstrates electrically switchable phase change antennas and metasurfaces that enable reversible, non-volatile spectral tuning of light in visible and near-infrared ranges, advancing optical device reconfigurability.

Contribution

It introduces a novel design of electrically-controlled phase change optical antennas and metasurfaces with multi-phase switching capabilities.

Findings

Achieved reversible spectral tuning in visible and near-infrared ranges.

Demonstrated strong, non-volatile optical switching.

Optimized antenna performance through thermal and optical design.

Abstract

The success of semiconductor electronics is built on the creation of compact, low-power switching elements that offer routing, logic, and memory functions. The availability of nanoscale optical switches could have a similarly transformative impact on the development of dynamic and programmable metasurfaces, optical neural networks, and quantum information processing. Phase change materials are uniquely suited to enable their creation as they offer high-speed electrical switching between amorphous and crystalline states with notably different optical properties. Their high refractive index has also been harnessed to fashion them into compact optical antennas. Here, we take the next important step by realizing electrically-switchable phase change antennas and metasurfaces that offer strong, reversible, non-volatile, multi-phase switching and spectral tuning of light scattering in the visible and near-infrared spectral ranges. Their successful implementation relies on a careful joint thermal and optical optimization of the antenna elements that comprise an Ag strip that simultaneously serves as a plasmonic resonator and a miniature heating stage.