Method for reducing stimulated brillouin scattering in waveguide systems and devices

Abstract

A waveguide configuration including a core having an index of refraction and a shear velocity, a first cladding extending about the core having a shear velocity which is less than that of the core and an index of refraction which is less than the core, a second cladding extending about the first cladding, the second cladding having a shear velocity which is greater than that of the first cladding, wherein an optical mode has an index of refraction greater than that of the second cladding, and a buffer extending about the second cladding.

What is claimed is:  
     
         1 . A waveguide configuration comprising: 
 a core having an index of refraction and a shear velocity;    a first cladding extending about the core having a shear velocity which is less than that of the core and an index of refraction which is less than the core;    a second cladding extending about the first cladding, the second cladding having a shear velocity which is greater than that of the first cladding, wherein an optical mode has an index of refraction greater than that of the second cladding; and    a buffer extending about the second cladding.    
     
     
         2 . The waveguide configuration of  claim 1  wherein a cross-sectional configuration of each of the core, the first cladding and the second cladding are substantially uniform along a length thereof.  
     
     
         3 . The waveguide configuration of  claim 1  further comprising a third cladding positioned between the second cladding and the buffer, the third cladding having an index of refraction less than that of each of the core, first cladding and second cladding.  
     
     
         4 . The waveguide configuration of  claim 1  wherein the first cladding is configured to be doped with fluorine and the second cladding is configured to be pure silica.  
     
     
         5 . The waveguide configuration of  claim 1  wherein the second cladding has a shear velocity that is less than that of the core and an index of refraction that is less than that of the core.  
     
     
         6 . The waveguide configuration of  claim 1  wherein the second cladding has a shear velocity that is greater than that of the core and an index of refraction that is greater than that of the core.  
     
     
         7 . The waveguide configuration of  claim 1  wherein the second cladding has a shear velocity that is approximately equal to that of the core and an index of refraction that is approximately equal to that of the core.  
     
     
         8 . A laser delivery system, the delivery system having reduced stimulated brillouin scattering effects, the system comprising: 
 a laser light source;    a pump light source;    a first core which guides light output from the laser light source and the pump light source and which is anti-guiding for acoustic waves;    a second core which confines the light output from the laser light source to the first core and guides light output from the pump light source, the second core guiding acoustic waves;    a cladding which confines the light output from the pump light source to the second core, the cladding guiding acoustic waves.    
     
     
         9 . The laser delivery system of  claim 8  wherein the first core has a shear velocity that is less than that of both the second core and the cladding.  
     
     
         10 . The laser delivery system of  claim 8  wherein the cladding has a shear velocity that is greater than that of the second core.  
     
     
         11 . The laser delivery system of  claim 8  further comprising a buffer.