A Novel Optical Coupler for Nanophotonics

Lead Research Organisation: University of Surrey
Department Name: ATI Physics

Abstract

During a previous EPSRC grant we developed a novel means of coupling light from an optical fibre to a very small semiconductor waveguides, of the order on 250nm in height, resulting in numerous publications and a patent. The predicted theoretical efficiency for the best device design was in excess of 90%, but when fabricated at the Southampton Microelectronics facility, the dimensions produced were incorrect due to an equipment failure, reducing the efficiency to a theoretical value of ~60%. Measured efficiency of this device was 55%, which is clearly very encouraging. Southampton University have agreed to provide devices of the correct dimensions that now need to be characterised in terms of coupling efficiency, polarisation and thermal performance. This one year project will characterise the devices, and will potentially demonstrate the highest coupling efficiency in the world into such a small device. This potentially world leading result will have immediate impact as this is a topical subject of research at present, particularly for novel applications such as optical interconnect.

Publications

10 25 50

publication icon
G Mashanovich (2007) Directional coupling to small silicon photonic waveguides in Journal of Optics A: Pure and Applied Optics

publication icon
Reed G (2006) Silicon Photonics: Are Smaller Devices Always Better? in Japanese Journal of Applied Physics

publication icon
Reed G (2006) Issues Associated With Polarization Independence in Silicon Photonics in IEEE Journal of Selected Topics in Quantum Electronics

 
Description A novel device design was developed and an associated patent was filed. AT the time this was regarded as an excellent step forward in the technology. Subsequent variation on the them were published by others
Exploitation Route Led to improved knowledge that has supported future grants. An improved variant of this type of device in now being used in a 2014 Programme grant
Sectors Digital/Communication/Information Technologies (including Software)

 
Title Dual grating assisted optical coupler 
Description An optical coupler comprises an input waveguide, an intermediate waveguide, an output waveguide, a first grating situated between the input and intermediate waveguides, and a second grating situated between the intermediate and output waveguides such that, in use, light propagating in the input waveguide is coupled into the intermediate waveguide with the assistance of the first grating, and thence is coupled into the output waveguide with the assistance of the second grating. The coupler is a directional coupler, in particular a dual grating-assisted directional coupler, and may be used to couple light between an optical fibre and an integrated semiconductor device, or between dissimilar waveguides. 
IP Reference US2006120667 
Protection Patent application published
Year Protection Granted 2006
Licensed No
Impact 1. An optical coupler comprising an input waveguide, an intermediate waveguide, an output waveguide, a first grating situated between the input and intermediate waveguides, and a second grating situated between the intermediate and output waveguides such that, in use, light propagating in the input waveguide is coupled into the intermediate waveguide wit the assistance of the first grating, and then is coupled into the output waveguide with the assistance of the second grating, wherein the i