We analyze the propagation of pulses in noncentrosymmetric crystals by applying high-frequency expansions techniques for Maxwell equations. As a rst application we give a closed-form expression for the anisotropic di raction operator. Given this expression we identify a critical con guration in biaxial crystals where the di raction reduces to a one-dimensional second-order operator for the ordinary wave instead of the standard transverse Laplacian. The beam propagation in such a con guration involves the generation of spatial solitons because of this anomalous onedimensional di raction. As a second application we present closed-form formulas for the interference patterns from biaxial crystal plates between two polarizers. These formulas agree with experimental patterns.
Josselin C. Garnier,
"Some applications of the anisotropic diffraction in biaxial crystals", Proc. SPIE 4271, Optical Pulse and Beam Propagation III, (12 April 2001); doi: 10.1117/12.424688; https://doi.org/10.1117/12.424688