Novel thick-grating beam-squeezing device in Ta2O5 corrugated planar waveguide

The fabrication and performance of a novel thick-grating beam-squeezing device in a Ta2O5 corrugated planar waveguide is described. The device, in which the design relies on consideration of the group velocities of the light inside the periodic guide at Bragg incidence, features a curved (hyperbolic) boundary transition between smooth and corrugated waveguide regions. A contraction ratio of about 30 is achieved.