Terahertz Time-Domain Spectroscopy Near-Field System

The terahertz time-domain spectroscopy (THz-TDS) near-field system combines a terahertz spectroscopy system with an AFM main unit for near-field operation. In the terahertz far field it offers a spectral bandwidth of 0.1–3 THz with a signal-to-noise ratio greater than 80 dB, and in the near field a spectral bandwidth of 0.5–2 THz. The system supports terahertz near-field imaging and spectroscopic studies.

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• The system integrates a terahertz time-domain spectrometer designed for near-field microscopy;
• The combination of the terahertz time-domain system and near-field microscopy achieves near-field terahertz spatial resolution better than 50 nm;
• Spectral coverage of the THz-TDS system: 0.1–3.0 THz in the far field and 0.5–2.0 THz in the near field, with an all-fiber optical path;
• Supports 1D (approach curves), 2D (AFM/s-SNOM images) and 3D scans;
• The system includes a femtosecond laser, an amplifier, a fast delay line and a compensation delay line. The fast delay line scans at > 10 Hz for spectral scanning, and the compensation delay line covers > 1500 ps for adjusting the spacing between the emitting and receiving antennas;
• The integrated time-domain spectrometer can be removed from the s-SNOM and used as a standalone far-field THz time-domain spectrometer. A three-point ball-and-groove magnetic mount ensures repeatable alignment of the spectrometer module;
• The far-field THz-TDS covers 0.1–3.0 THz with a signal-to-noise ratio > 80 dB.