GaAs Mid-IR Electrically Tunable Metasurfaces.

In this work, we explore III-V based metal-semiconductor-metal structures for tunable metasurfaces. We use an epitaxial transfer technique to transfer a III-V thin film directly on metallic surfaces, realizing III-V metal-semiconductor-metal (MSM) structures without heavily doped semiconductors as substitutes for metal layers. The device platform consists of gold metal layers with a p-i-n GaAs junction.

Symmetry breaking of dark-mode metamaterials for voltage-switchable infrared absorption.

We propose electrically reconfigurable absorbers with switchable narrowband resonances in the infrared. Our absorbers consist of two coupled, identical resonators and support a dark supermode. We show that by dynamically breaking the symmetry of the system, the dark supermode can be made to couple to an incoming plane wave, producing a narrowband absorption peak in the spectrum.

Monolithic III-V on Metal for Thermal Metasurfaces.

It has been proposed that metal-semiconductor-metal (MSM) structures can be used to tune the absorptivity of a metasurface at infrared wavelengths. Indium arsenide (InAs) is a low-band-gap, high-electron-mobility semiconductor that may enable rapid index tuning for dynamic control over the infrared spectrum. However, direct growth of III-V thin films on top of metals has typically resulted in small-grain, polycrystalline materials that are not amenable to high-quality devices.