Titanium free optical waveguides in lithium niobate produced by Etching During Indiffusion of titanium (EDIT)

Abstract

Numerous techniques to fabricate optical waveguides in LiNbO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> have been reported, which include Li <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O out diffusion, metal in-diffusion, ion exchange, proton exchange, strain induced waveguides, ion implantation/irradiation, using the photo-refractive effect and ultrafast or UV laser writing. We have recently reported a technique to surface machine LiNbO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> etching during the indiffusion of Ti (EDIT), where one X cut sample is prepared with a patterned film of titanium. This is then placed in contact with another unprocessed X-cut sample and the pair is annealed in a wet oxygen atmosphere. After annealing, the originally unpatterned wafer is etched corresponding to the Ti patterns on the other wafer. In this work, we report on the observation of waveguiding in LiNbO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> that has been EDIT patterned.