Imaging and Spectroscopic Sensing with Low-Repetition-Rate Terahertz Pulses and GaN TeraFET Detectors

D. Voß1, W. Zouaghi1, M. Jamshidifar2, S. Boppel1,5, C. McDonnell3, J.R.P. Bain3, N. Hempler3, G.P.A. Malcolm3, G.T. Maker3, M. Bauer1, A. Lisauskas1,4, A. Rämer5, S.A. Shevchenko5, W. Heinrich5, V. Krozer1,5, H.G. Roskos1

Published in:

Int. J. Infrared Millimeter Terahertz Waves, vol. 39, no. 3, pp. 262-272 (2018).

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Abstract:

Aiming for non-destructive testing and security applications, we investigate transmission-mode imaging and spectroscopic sensing using terahertz (THz) pulses from a commercial optical parametric oscillator (OPO) in combination with THz detectors based on antenna-coupled field-effect transistors (TeraFETs). The Q-switched OPO generates quasi-continuous-wave THz pulses with a peak power of up to 1 W at a repetition rate between 12 and 90 Hz. The pulses are frequency-tunable between 0.7 and 2.6 THz with a typical linewidth of 50 GHz. We explore detection with fast GaN/AlGaN TeraFETs which hold the potential for multi-pixel and homodyne detection.

1 Physikalisches Institut, Goethe-University Frankfurt, Frankfurt am Main, Germany
2 Lehrstuhl für Höchstfrequenztechnik, University of Siegen, Siegen, Germany
3 M Squared Lasers, Glasgow, Scotland
4 Center for Physical Sciences and Technology, Vilnius University, Vilnius, Lithuania
5 Ferdinand-Braun-Institut, Leibniz-Institut für Höchstfrequenztechnik (FBH), Berlin, Germany

Keywords:

THz detection, Optical parametric oscillator, Field effect transistor, THz imaging, THz spectorscopy.