Terahertz generation, and detection

Sinyukov, A. M. Hayden, L. M., Generation and detection of terahertz radiation with multilayered electro optic polymer films, Opt. Lett. 2002, 27, 55 57... 

Terahertz imaging approaches have typically used either short-pulsed laser or continuous wave (CW) THz generation and detection. The short-pulsed method usually involves the generation and detection of sub-picosecond THz pulses using either photoconductive antenna structures or optical rectification in a non-linear crystal. Pulsed sources seem to be more favorable (in particular for close proximity applications) because they can be used for acquiring depth information. Spectral information is retrieved by a Fourier transform of the time-domain data to the frequency domain. 

Terahertz Signal Generation and Detection, Optical Rectification, and Electro-Optic Sensors... 

Generation and Detection of the Terahertz Radiation Using a Photoconductive Antenna Element... 

Tani, M., Herrmann, M. and Sakai, K. (2002) Generation and detection of terahertz pulsed radiation with photoconductive antennas and its application to imaging. Meas. Sci. Technol, 13, 1739-1745. 

The terahertz radiation that has passed through the sample is detected with an optical system having essentially the same structure as the optical system for generating the terahertz radiation and focusing it onto the sample, as depicted in Figure 19.2. The terahertz radiation that has passed through the sample is focused onto the terahertz-radiation detection... 

However, it is not possible to determine directly Ej (t) and 4> t) of the terahertz radiation, because the terahertz radiation is emitted as an extremely short pulse. For this reason, as illustrated schematically in Figure 19.4, time delays are instigated between the laser pulses for generating the terahertz radiation and those for detecting the terahertz radiation. The shape of the terahertz radiation on the time axis is determined by scanning the delay time of the laser pulses. 

Terahertz Generation, Detection and Time-Resolved Terahertz Spectroscopy Setup... 

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