Plasmonic funnel for focused optical delivery to a metallic medium

Abstract

An apparatus includes a transducer including a plasmonic funnel having first and second ends with the first end having a smaller cross-sectional area than the second end, and a first section positioned adjacent to the first end of the plasmonic funnel, and a first waveguide having a core, positioned to cause light in the core to excite surface plasmons on the transducer.

What is claimed is: 
     
         1 . An apparatus comprising:
 a transducer including a plasmonic funnel including first and second ends with the first end having a smaller cross-sectional area than the second end, and a first section positioned adjacent to the first end of the plasmonic funnel; and   a first waveguide having a core, positioned to cause light in the core to excite surface plasmons on the transducer.   
     
     
         2 . The apparatus of  claim 1 , wherein a portion of the first waveguide core is positioned adjacent to a side of the transducer such that light in the waveguide core is evanescently coupled to the transducer. 
     
     
         3 . The apparatus of  claim 1 , wherein the transducer further comprises:
 a second section positioned adjacent to the second end of the plasmonic funnel.   
     
     
         4 . The apparatus of  claim 3 , wherein an end of the first waveguide core is positioned adjacent to an end the transducer such that light in the waveguide core is end fire coupled to the transducer. 
     
     
         5 . The apparatus of  claim 3 , wherein the second section includes first and second ends with the first end having a smaller cross-sectional area than the second end, with the second end being positioned adjacent to the second end of the plasmonic funnel. 
     
     
         6 . The apparatus of  claim 3 , further comprising:
 a phase changing element positioned along a side of the second section.   
     
     
         7 . The apparatus of  claim 6 , wherein the phase changing element comprises one of:
 a stub, an indent, or a protrusion.   
     
     
         8 . The apparatus of  claim 1 , wherein the first waveguide comprises one of:
 a channel waveguide, a solid immersion mirror, or a mode index lens.   
     
     
         9 . The apparatus of  claim 8 , further comprising:
 a polarization rotator adjacent to the first waveguide.   
     
     
         10 . The apparatus of  claim 9 , wherein the polarization rotator comprises one of:
 first and second plasmonic stubs adjacent to diagonally opposite edges of the dielectric channel waveguide.   
     
     
         11 . The apparatus of  claim 1 , further comprising:
 a first magnetic pole positioned adjacent to a side of the first section of the transducer.   
     
     
         12 . The apparatus of  claim 11 , further comprising:
 a second magnetic pole; and   a plasmonic shield positioned between the second magnetic pole and the transducer.   
     
     
         13 . The apparatus of  claim 12 , wherein a gap between the plasmonic shield and the transducer is filled with dielectric material. 
     
     
         14 . The apparatus of  claim 1 , further comprising:
 first and second plasmonic shields positioned adjacent to opposite sides of the first portion.   
     
     
         15 . An apparatus comprising:
 a transducer including a plasmonic funnel including first and second ends with the first end being narrower than the second end, a first plasmonic waveguide positioned adjacent to the first end of the plasmonic funnel, and a second plasmonic waveguide positioned adjacent to the second end of the plasmonic funnel; and   a phase changing element positioned along a side of the second plasmonic waveguide.   
     
     
         16 . The apparatus of  claim 15 , wherein the phase changing element comprises one of:
 a stub, an indent, or a protrusion.   
     
     
         17 . An apparatus comprising:
 a recording medium;   a recording head having a transducer including a plasmonic funnel having first and second ends with the first end having a smaller cross-sectional area than the second end, and a first section positioned adjacent to the first end of the plasmonic funnel, and a first waveguide having a core, positioned to cause light in the core to excite surface plasmons on the transducer; and   a positioning means for positioning the recording head adjacent to the storage medium.   
     
     
         18 . The apparatus of  claim 17 , wherein a portion of the first waveguide core is positioned adjacent to a side of the transducer such that light in the waveguide core is evanescently coupled to the transducer. 
     
     
         19 . The apparatus of  claim 17 , wherein the transducer further comprises:
 a second section positioned adjacent to the second end of the plasmonic funnel.   
     
     
         20 . The apparatus of  claim 19 , wherein an end of the first waveguide core is positioned adjacent to an end the transducer such that light in the waveguide core is end fire coupled to the transducer.