Patent ID: 7463807

Claim:
A waveguide configuration comprising: a optical core having an optical core radial thickness and a core index of refraction, and, at least one optical cladding surrounding the core, the at least one optical cladding having a cladding index of refraction, cooperating to define an optical mode, wherein the effective index of refraction of the optical mode is greater than the cladding index of refraction; an acoustic core having at least two regions, a first region having a first region radial thickness and a first region acoustic velocity, and, a second region surrounding the first region having a second region radial thickness and a second region acoustic velocity, and an acoustic cladding surrounding the acoustic core having an acoustic cladding acoustic velocity; wherein the first region radial thickness is smaller than the optical core radial thickness and the sum of the first region radial thickness and the second region radial thickness is greater than the optical core radial thickness; and the first region acoustic velocity is greater than the second region acoustic velocity and the acoustic cladding acoustic velocity is greater than the second region acoustic velocity.