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All-air terahertz spectrometer

Trainee Achievements

All-air terahertz spectrometer

The methods that IGERT trainee Nick Karpowicz introduced for the coherent detection of terahertz waves in gases have been extensively applied in the Center for Terahertz Research at Rensselaer. A new reflection spectroscopy system with bandwidth reaching from 100 GHz to nearly 20 THz has become a popular tool in the laboratory and has lead to several recent publications. The construction of this system required the efforts of students of several different backgrounds, in optical and electrical engineering (to construct the high-voltage modulator required for the heterodyne technique), as well as physics to analyze the optimal system configuration. Due to these combined efforts, the all-air terahertz spectrometer is a unique system with capabilities (high electric field combined with greater than 10 THz bandwidth) not found in any other time-domain THz spectrometer available today.