Research Article
Vol. 59, No. 6 / 20 February 2020 / Applied Optics
1641
Guided terahertz pulse reflectometry with double
photoconductive antenna
Mingming Pan,1 Quentin Cassar,1 Frédéric Fauquet,1 Georges Humbert,2
Patrick Mounaix,1 AND Jean-Paul Guillet1,*
1IMS Laboratory, University of Bordeaux, UMR5218, 351 cours de la Libération, 33405 Talence, France
2XLIMResearch Institute, UMR 7252CNRS/University of Limoges, 123 av. A. Thomas, 87060 Limoges, France
*Corresponding author: jean-paul.guillet@u-bordeaux.fr
Received 8 November 2019; revised 9 January 2020; accepted 10 January 2020; posted 13 January 2020 (Doc. ID 381646);
published 13 February 2020
Developments toward the implementation of a terahertz pulse imaging system within a guided reflectometry
configuration are reported. Two photoconductive antennas patterned on the same LT-GaAs active layer in associ-
ation with a silica pipe hollow-core waveguide allowed us to obtain a guided optics-free imager. Besides working
in a pulsed regime, the setup does not require additional optics to focus and couple the terahertz pulses into the
waveguide core, simplifying the global implementation in comparison with other reported guided terahertz reflec-
tometry systems. The system is qualified for imaging purposes by means of a 1951 USAF resolution test chart. An
image resolution, after a 53 mm propagation length, by about 0.707 LP/mm over the 400–550 GHz integrated
frequency band, was obtained, thus providing a promising basis to pursue efforts toward compact guided pulse
imagers for sample inspection within the terahertz range. © 2020 Optical Society of America
https://doi.org/10.1364/AO.381646
1. INTRODUCTION
The terahertz frequency region has been attracting an increasing
amount of attention over the past decades owing to the abilities
of these waves to penetrate opaque structures [1] and to identify
specific materials through their spectral features. Relevant tech-
nologies such as time-domain spectroscopy (TDS) and THz
imaging have been used for various applicatio