Beam profiling of a commercial lens-assisted terahertz time domain spectrometer
File(s)
Published version
OA Location
Author(s)
Freer, Suzanna
Gorodetsky, Andrei
Navarro-Cia, Miguel
Type
Journal Article
Abstract
To undertake THz spectroscopy and imaging, and accurately design and predict the performance of quasi-optical components, knowledge of the parameters of the beam (ideally Gaussian) emitted from a THz source is paramount. Despite its proliferation, relatively little work has been done on this in the frame of broadband THz photoconductive antennas. Using primarily pinhole scanning methods, along with stepwise angular spectrum simulations, we investigate the profile and polarization characteristics of the beam emitted by a commercial silicon-lensintegrated THz photoconductive antenna and collimated by a TPX (polymethylpentene) lens. Our study flags the limitations of the different beam profiling methods and their impact on the beam Gaussianity estimation. A non-Gaussian asymmetric beam is observed, with main lobe beam waists along x and y varying from 8.4 ± 0.7 mm and 7.7±0.7 mm at 0.25THz,to1.4±0.7 mm and 1.4 ± 0.7 mm at 1 THz, respectively. Additionally, we report a maximum cross-polar component relative to the ON-axis co-polar component of -11.6 dB and -21.2 dB, at 0.25 THz and 1 THz, respectively.
Date Issued
2021-01-01
Date Acceptance
2020-09-16
Citation
IEEE Transactions on Terahertz Science and Technology, 2021, 11 (1), pp.90-100
ISSN
2156-342X
Publisher
Institute of Electrical and Electronics Engineers
Start Page
90
End Page
100
Journal / Book Title
IEEE Transactions on Terahertz Science and Technology
Volume
11
Issue
1
Copyright Statement
© 2020 The Author(s). This work is licensed under a Creative Commons Attribution 4.0 License. For more information, see https://creativecommons.org/licenses/by/4.0/
License URL
Identifier
http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000606582500009&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=1ba7043ffcc86c417c072aa74d649202
Subjects
Science & Technology
Technology
Physical Sciences
Engineering, Electrical & Electronic
Optics
Physics, Applied
Engineering
Physics
Beam profile
edge diffraction
Gaussian beam
imaging
quasi-optics
terahertz
time-domain spectrometer
Publication Status
Published
Date Publish Online
2020-09-24