Optimization and applications of air-plasma dynamic aperture-based terahertz microscopy

Area of Science:

• Optics and Photonics
• Materials Science
• Spectroscopy

Background:

• Terahertz (THz) microscopy offers high spatial resolution and spectral information for far-infrared inspection.
• Existing THz microscopy techniques often require close sample proximity, limiting certain applications.

Purpose of the Study:

• To develop a novel air-plasma dynamic aperture-based THz near-field technique for sub-wavelength THz imaging.
• To enhance system performance, including reduced measurement time and improved signal-to-noise ratio.
• To demonstrate advanced applications of THz microscopy.

Main Methods:

• Implementation of an air-plasma dynamic aperture for THz near-field generation.
• Improvement of the measurement mode and application of a data processing method.
• Development of a THz microscopy system capable of sub-wavelength imaging without sample contact.

Main Results:

• Achieved sub-wavelength THz imaging without approaching the sample surface.
• Reduced measurement time by approximately 4 times.
• Enhanced the signal-to-noise ratio by more than 6 times compared to previous methods.
• Demonstrated imaging of isolated objects, identification of semifluid chemicals, and characterization of semifluid surfaces.

Conclusions:

• The developed THz near-field technique significantly matures THz microscopy.
• The improved system broadens the application scope of THz microscopy in fundamental research and industrial inspection.
• The technique enables non-contact, high-resolution imaging and analysis of various materials.