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Subwavelength Terahertz Resonance Imaging (STRING) for Molecular Fingerprinting
Taewoo Ha1, Daehan Yoo2, Chaejeong Heo1,3
1Center for Integrated Nanostructure Physics, Institute for Basic Science, Sungkyunkwan University, Suwon16419, Republic of Korea.
Nano Letters
|December 12, 2022
Summary
Subwavelength terahertz resonance imaging (STRING) offers ultrasensitive molecular fingerprinting by combining ring resonators with near-field spectroscopy. This breakthrough enhances sensitivity by up to 10 orders of magnitude for biochemical sensing and materials science applications.
Area of Science:
- Terahertz (THz) spectroscopy and imaging
- Biochemical sensing
- Materials science
Background:
- Subwavelength THz imaging is crucial for biochemical sensing and materials science.
- Sensitive spectral fingerprinting in the THz domain is limited by weak light-matter interactions.
Purpose of the Study:
- To demonstrate a novel subwavelength THz resonance imaging (STRING) technique.
- To achieve ultrasensitive molecular fingerprinting overcoming current limitations.
Main Methods:
- STRING combines individual ring-shaped coaxial single resonators with near-field spectroscopy.
- Local field enhancement and near-field effects contribute to sensitivity gains.
Main Results:
- Ultrasensitive molecular fingerprinting was achieved using STRING.
- Sensitivity was enhanced by up to 10 orders of magnitude compared to far-field THz measurements.
- Spectral fingerprints of α-lactose and maltose monohydrate isomers were successfully obtained.
Conclusions:
- The STRING platform enables practical and sensitive THz spectroscopy.
- STRING facilitates fingerprinting and spectral imaging of molecules and nanoparticles.
- This technique significantly advances THz-based analytical capabilities.
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