Electrically Reconfigurable Nonvolatile Flatband Absorbers in the Mid-Infrared with Wide Spectral Tuning Range.

Area of Science:

• Photonics and Metamaterials
• Optoelectronics
• Materials Science

Background:

• Controlling infrared absorption on demand is a significant challenge in subwavelength photonics.
• Existing infrared microstructures often rely on volatile phase-change materials, requiring continuous power.

Purpose of the Study:

• To experimentally demonstrate an electrically switchable plasmonic metasurface for infrared absorption control.
• To achieve on-demand, zero-static-power operation in the 3–5 μm wavelength range.

Main Methods:

• Fabrication of a plasmonic metasurface utilizing the phase-change material Ge₂Sb₂Te₅.
• In situ electrical switching of optical absorption.
• Characterization of absorptivity, angle-of-incidence independence, and switching cycles.

Main Results:

• Demonstrated electrically switchable absorption in the 3–5 μm range with Ge₂Sb₂Te₅.
• Achieved zero static power operation due to the non-volatile nature of the phase-change material.
• Exhibited robust tuning of absorptivity, independent of incidence angle, due to deep-subwavelength field localization.
• Successfully performed 26 reversible switching cycles using electrical pulses.

Conclusions:

• The developed plasmonic metasurface offers a novel approach for on-demand infrared absorption control.
• The device's zero static power and robust performance make it a promising stepping stone for next-generation midwave infrared photonics.