Enhanced trace-amount terahertz vibrational absorption spectroscopy using surface spoof polarization in metasurface...

Area of Science:

• Physics
• Materials Science
• Spectroscopy

Background:

• Terahertz (THz) absorption spectroscopy is crucial for label-free molecular fingerprinting.
• Enhancing broadband spectral signals is a major challenge for trace-amount THz analysis.

Purpose of the Study:

• To propose and numerically simulate a new sensing method for enhancing THz absorption signals.
• To enable sensitive detection of trace-amount analytes using THz spectroscopy.

Main Methods:

• Utilizing geometry scanning of metal metasurfaces.
• Leveraging spoof surface polarization sharp resonances.
• Performing numerical simulations to validate the approach.

Main Results:

• Achieved an absorption enhancement factor of approximately 200 times.
• Demonstrated explicit identification of trace-amount analytes, like lactose films.
• Covered an ultra-wide terahertz band spectrum.

Conclusions:

• The proposed method offers a novel solution for enhancing wideband THz absorption spectra.
• This technique paves the way for detecting trace-amount chemical, organic, and biomedical materials in the THz regime.