Paul Dean, Aziati H. Awang, Iman Kundu, Raed Alhathlool, Suraj P. Khanna, Lianhe H. Li, Andrew Burnett, Edmund H. Linfield, and A. Giles Davies
We present experimental evidence for a photothermoelastic response in zincblende crystals illuminated by quantum cascade laser sources in the frequency range 2.2–2.9 THz. Results obtained using an optically balanced sampling arrangement indicate a mechanism whereby the stress distribution established through localized heating of the crystal induces a change in optical birefringence via the photoelastic response of the crystal. A full mathematic model of this photothermoelastic mechanism in (110)-orientated crystals is presented, and shown to agree well with experimental measurements of the magnitude, and the orientational and spatial dependencies of the sampled signal in ZnTe and GaP crystals.
© 2013 Optical Society of America
No comments:
Post a Comment