Walsh, D.A. and Cliffe, M.J. and Pan, R. and Snedden, E.W. and Graham, D.M. and Gillespie, W.A. and Jamison, S.P. (2014) Role of misalignment-induced angular chirp in the electro-optic detection of THz waves. Optics Express, 22 (10). pp. 12028-12037. ISSN 1094-4087
Full text not available from this repository.Abstract
A general description of electro-optic detection including non-collinear phase matching and finite transverse beam profiles is presented. It is shown theoretically and experimentally that non-collinear phase matching in ZnTe (and similar materials) produces an angular chirp in the χ(2)-generated optical signal. Due to this, in non-collinear THz and probe arrangements such as single-shot THz measurements or through accidental misalignment, measurement of an undistorted THz signal is critically dependent on having sufficient angular acceptance in the optical probe path. The associated spatial walk-off can also preclude the phase retardation approximation used in THz-TDS. The rate of misalignment-induced chirping in commonly used ZnTe and GaP schemes is tabulated, allowing ready analysis of a detection system.