Fiber-to-chip coupler designed using an optical transformation.

Department of Electrical Engineering and Computer Science, Vanderbilt University, 37235, USA.
Optics Express (Impact Factor: 3.53). 06/2012; 20(13):14705-13. DOI: 10.1364/OE.20.014705
Source: PubMed

ABSTRACT An integrated silicon photonics coupler for fiber to waveguide conversion was designed employing a transformation optics approach. Quasi-conformal mapping was used to obtain achievable material properties, which were realized by a distorted hexagonal lattice of air holes in silicon. The coupler, measuring only 10 μm in length and fabricated with a single-step lithography process, exhibits a peak simulated transmission efficiency of nearly 100% for in-plane mode conversion and a factor of 5 improvement over butt coupling for fiber to waveguide mode conversion in experimental testing.

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