Three-Dimensional Wide-Bandwidth Quantum Energy Truncation Terahertz Coherence Tomography

Area of Science:

• Physics
• Chemistry
• Materials Science

Background:

• Conventional continuous-wave (CW) terahertz (THz) imaging lacks spectroscopic specificity and relies on angular scanning.
• Extracting detailed molecular information and subsurface structures simultaneously is challenging with existing THz techniques.

Purpose of the Study:

• To introduce a novel quantum energy truncation terahertz coherence tomography (QET-TCT) technique.
• To enable highly localized extraction of molecular-species-specific THz responses for 3D material characterization.

Main Methods:

• Exploiting resonant photon loss when THz energy matches molecular vibration quanta.
• Recording and mapping reflected THz radiation into depth-coded image sequences.
• Retrieving subsurface structural information and molecular fingerprints to construct 3D tomograms.

Main Results:

• Directly correlating molecular excitation spectra with depth information, overcoming CW THz imaging limitations.
• Achieving rapid, three-dimensional THz imaging with selective sensitivity to discrete molecular quantum energy transitions.
• Successfully constructing 3D tomograms revealing both structural and molecular composition data.

Conclusions:

• QET-TCT offers a significant advancement in nondestructive material characterization.
• The technique provides new opportunities for analyzing material refractive indices, molecular composition, and subsurface structures.
• This method enables precise, localized THz imaging with enhanced spectroscopic specificity.