Double-Resolved Beam Steering by Metagrating-Based Tamm Plasmon Polariton

Area of Science:

• Optics and Photonics
• Metamaterials
• Plasmonics

Background:

• Tamm plasmon polaritons (TPPs) are surface electromagnetic waves supported at the interface of a metal and a dielectric.
• Subwavelength gratings patterned on Bragg reflectors can support TPPs and exhibit unique optical properties.

Purpose of the Study:

• To demonstrate dynamic control over the phase and amplitude of reflected light from a metagrating.
• To investigate the resonant coupling between TPPs and plane waves for tunable optical responses.
• To explore the potential for electrical switching of diffracted beams and enhanced angular resolution.

Main Methods:

• Fabrication of a subwavelength grating on a Bragg reflector to support TPPs.
• Utilizing a transparent conductive oxide layer for refractive index modulation via applied bias voltage.
• Characterization of the reflected wave's phase and amplitude modulation.
• Demonstration of electrical switching of ±1st order diffracted beams.

Main Results:

• Achieved dynamic control of reflected wave phase and amplitude through TPP resonant coupling.
• Demonstrated electrical tunability of optical response by modulating the refractive index of the transparent conductive oxide layer.
• Showcased electrical switching of diffracted beams.
• Proved the possibility of doubling angular resolution in beam steering using asymmetric phase distributions.

Conclusions:

• The proposed metagrating structure enables efficient dynamic control of reflected light properties.
• Electrical modulation of TPPs offers a promising pathway for advanced optical devices like beam steerers.
• The demonstrated technique enhances angular resolution, paving the way for improved optical sensing and imaging.