Composite waveguide on Nd-glass by ion exchange

Abstract

We have fabricated and tested coupled integrated coupled and branching waveguide lasers in Nd glass substrates1 . By making two or more parallel diffused channel or ridge waveguides close together on rare-earth doped glass substrates as shown in Fig's 1 , a set of coupled waveguide lasers can be fabricated which produce two closely spaced light waves, the symmetric and anti symmetric modes of the structure. The difference between their frequencies is in the microwave regime. Such devices can serve as single-sideband optical carrier sources. We have fabricated both diffused channel waveguides as shown in Fig. 1 a and ridge waveguides as shown in Fig. lb. The ridge waveguides can be bend through smaller radii than diffused wave guides for the same loss of light. III a) Diffused cannel waveguides b) Ridge waveguides Fig. 1. Cross section of evanescent coupled waveguides. The cross section of waveguides fabricated by diffusing Ag into the Nd-glass substrate is shown in a. The cross section of a pair of coupled ridge waveguides fabricated on Nd-glass substrate are shown in b.A branching structure as shown in Fig. 2. is usually needed in actual devices for routing purposes. With proper reflectivity at the end faces of each waveguide, the structure in Fig. 2a 64 / SPIE Vol. 2749 O-8194-2130-8/96/$6.OO Downloaded From: http://proceedings.spiedigitallibrary.org/ on 06/17/2016 Terms of Use: http://spiedigitallibrary.org/ss/TermsOfUse.aspx