Related Experiment Video
Updated: Apr 16, 2026

A Multimodal Wide-Field Fourier-Transform Raman Microscope
Published on: December 30, 2025
GaP Raman Terahertz high accuracy spectrometer and its application to detect organic and inorganic crystalline
Jun-Ichi Nishizawa1, Ken Suto1, Tetsuo Sasaki1
1Semiconductor Research Institute, Sendai, Japan .
Abstract:
One of the most important uses of THz spectrometry is to detect defects in molecular structure or in crystals efficiently. We applied GaP Raman THz (GRT) spectrometer to detect and evaluate defects in inorganic and organic materials. High THz-wave absorption due to high defect density of GaSe crystal lowered the efficiency of THz wave generation, when the crystal is used as nonlinear material for DFG (Difference Frequency Generation). Defects in organic molecules could be observed as changes in frequency, intensities of the absorption, and broadenings of the spectra.
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