Wavelength multiplexing infrared metasurfaces for protein recognition and trace detection

Area of Science:

• Optics and Photonics
• Nanotechnology
• Sensing Technology

Background:

• Infrared metasurfaces offer unique optical properties for broadband, label-free sensing.
• Implementing wavelength multiplexing in broadband infrared sensors is challenging due to difficulties in exciting and tuning high Q resonances.

Purpose of the Study:

• To present a dual resonant metasurface for independent spectral control in near- and mid-infrared regions.
• To demonstrate a metasurface capable of wavelength multiplexing and polarization-dependent sensing for enhanced applications.

Main Methods:

• Utilized a metal-dielectric-metal plasmonic grating and a dielectric-metal channel for dual resonance.
• Adjusted vertical and horizontal structures to independently tune spectral responses in different infrared regions.
• Implemented a polarization-dependent strategy for dual-resonance control.

Main Results:

• Achieved independent spectral modification in near-infrared and mid-infrared regions.
• Demonstrated robust spectral regulation and a polarization-dependent dual-resonance strategy.
• Showcased refractive index sensing in the second near-infrared window and vibrational spectroscopy in mid-infrared.

Conclusions:

• The proposed dual resonant metasurface offers a competitive advantage for refractive index sensing and vibrational spectroscopy.
• The metasurface enables protein concentration sensing and dynamic monitoring, enhancing mid-infrared absorption.
• This technology presents a novel approach for high-performance integrated photonics sensors in the broadband infrared region.