Ring-Geometry Photodetector Designs For High-Sensitivity And High-Speed Detection Of Optical Signals For Fiber Optic And Integrated Optoelectronic Devices

Abstract

A semiconductor photodetector comprising a closed loop configured to receive light from an external source adapted to trap light within said closed loop until absorption by the semiconductor.

What is claimed is: 
     
         1 . A semiconductor photodetector comprising: a closed loop, said closed loop configured to receive light from an external source; and said closed loop adapted to trap light within said closed loop until absorption by the semiconductor. 
     
     
         2 . The semiconductor photodetector of  claim 1  wherein said closed loop recirculates light received from an external source. 
     
     
         3 . The semiconductor photodetector of  claim 1  wherein said closed loop recirculates light received from an external source until all light is absorbed by the semiconductor. 
     
     
         4 . The semiconductor photodetector of  claim 1  wherein said closed loop is a ring 
     
     
         5 . The semiconductor photodetector of  claim 1  wherein light is captured and re-circulated in the photodetector using a curved ridge-waveguide ring resonator. 
     
     
         6 . The semiconductor photodetector of  claim 1  wherein light is captured and re-circulated in the photodetector using straight waveguides and mirrors. 
     
     
         7 . The semiconductor photodetector of  claim 1  wherein light is captured and re-circulated in the photodetector using straight waveguides and mirrors, said waveguides and mirrors redirecting light into said closed loop. 
     
     
         8 . The semiconductor photodetector of  claim 1  wherein light is captured and re-circulated in the photodetector using a photonic crystal structure. 
     
     
         9 . A method capturing light in a semiconductor photodetector comprising the following steps: directing light into a closed loop; and trapping light from an external source within said closed loop until absorption by the semiconductor. 
     
     
         10 . The method of  claim 9  further comprising the step of recirculating light received from an external source in said closed loop until absorption by the semiconductor. 
     
     
         11 . The method of  claim 10  wherein said light is recirculated until all light from an external source is absorbed by the semiconductor. 
     
     
         12 . The method of  claim 10  wherein said closed loop is a ring 
     
     
         13 . The method of  claim 10  wherein light is captured and re-circulated in the photodetector using a curved ridge-waveguide ring resonator. 
     
     
         14 . The method of  claim 10  wherein light is captured and re-circulated in the photodetector using straight waveguides and mirrors. 
     
     
         15 . The method of  claim 10  wherein light is captured and re-circulated in the photodetector using straight waveguides and mirrors, said waveguides and mirrors redirecting light into said closed loop. 
     
     
         16 . The method of  claim 10  using a photonic crystal structure.