Four phase-sensitive imaging methods (Talbot, phase contrast, Sagnac, and polarization gating) used for detecting terahertz-frequency waves in structured lithium niobate slabs are compared analytically and experimentally. It is demonstrated that both phase contrast and a self-compensating polarization gating geometry can generate in-focus images of the sample and quantitatively measure the terahertz electric field. Of these two methods polarization gating has better signal-to-noise ratio and so is preferred for most situations, while phase contrast imaging has better spatial resolution and so is preferred for measurements involving fine structures or near-field effects.
© 2010 Optical Society of America
Original Manuscript: July 6, 2010
Manuscript Accepted: September 3, 2010
Published: October 18, 2010
Christopher A. Werley, Qiang Wu, Kung-Hsuan Lin, C. Ryan Tait, August Dorn, and Keith A. Nelson, "Comparison of phase-sensitive imaging techniques for studying terahertz waves in structured LiNbO3," J. Opt. Soc. Am. B 27, 2350-2359 (2010)
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