Open AccessTerahertz Bessel-Gauss beams of radial and azimuthal polarization from microstructured photoconductive antennas
Author(s) -
Stephan Winnerl,
B. Zimmermann,
F. Peter,
Harald Schneider,
Manfred Helm
Publication year - 2009
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.17.001571
Subject(s) - optics , terahertz radiation , physics , polarization (electrochemistry) , radial polarization , linear polarization , materials science , laser , laser beam quality , laser beams , chemistry
We report on emission and detection of pulsed terahertz radiation of radial and azimuthal polarization by microstructured photoconductive antennas. To this end the electrode geometry of the emitter is inverse to the desired THz field pattern and a second periodic structure prevents destructive interference effects. Beam profiles of freely propagating THz waves are studied for divergent and refocused beams. They can be well described as the lowest order Bessel-Gauss modes with a divergence comparable to linearly polarized Gaussian beams. Additionally, mode sensitive detection is demonstrated for radially polarized radiation.