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Characterizing Far-infrared Laser Emissions and the Measurement of Their Frequencies
Published on: December 18, 2015
Simple laser velocimeter that uses photoconductive semiconductors to measure optical frequency differences
Applied Optics
|November 10, 2010
Abstract:
The dc photocurrents generated by steady-state moving space-charge fields inside photoconductive semiconductors containing deep level donors and traps can be used to determine the relative frequency differences between the two interfering optical fields that establish the space-charge fields. A simple laser velocimeter that uses a semi-insulating GaAs:Cr sample to detect the Doppler frequency shift between two laser beams is demonstrated.
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