Classical masking aperture methods are found to be mostly inaccurate to determine the terahertz beam size in terahertz time-domain spectroscopy (TDS) experiments, owing to complex diffraction effects. Here, we present a simple and reliable method for measuring beam waists in terahertz TDS. It is based on the successive diffraction by an opaque disk followed by a small circular aperture.
© 2010 Optical Society of America
Lasers and Laser Optics
Original Manuscript: December 1, 2009
Revised Manuscript: February 1, 2010
Manuscript Accepted: February 4, 2010
Published: March 17, 2010
Alexander Podzorov, Antoine Wojdyla, and Guilhem Gallot, "Beam waist measurement for terahertz time-domain spectroscopy experiments," Opt. Lett. 35, 901-903 (2010)