Multifrequency continuous wave terahertz spectroscopy for absolute thickness determination

Scheller, Maik; Baaske, Kai; Koch, Martin
April 2010
Applied Physics Letters;4/12/2010, Vol. 96 Issue 15, p151112
Academic Journal
We present a tunable multifrequency continuous wave terahertz spectrometer based on two laser diodes, photoconductive antennas, and a coherent detection scheme. The system is employed to determine the absolute thickness of samples utilizing a proposed synthetic difference frequency method to circumvent the 2Ï€ uncertainty known from conventional photomixing systems while preserving a high spatial resolution.


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