1. Coupled Resonator Optical Waveguides (CROWs) Fatemeh Soltani Fatemeh.soltani@mail.mcgill.ca McGill University Photonics Systems Group CMC workshop, July 2012

2. An Illustration of CROW 2 Scheuer, G. T. Paloczi, J. K. S. Poon and A. Yariv, “Coupled Resonator Optical Waveguides: Towards Slowing and Storing of Light”, Opt. Photon. News, Vol. 16 (2005) 36

3. Why CREW ? Engineer the dispersion properties of a CROW The ability to realize ultra-slow group velocities Applications in delay lines, optical memories and all-optical switching. Simple analytic expressions for the time delay, usable bandwidth and overall losses in CROW delay lines. Good quantitative agreement between the theoretical transmission function obtained by transfer matrix formalism. The measurement of a CROW interferometer realized in polymer material. 3

4. Travelling wave in a finite CROW 4

5. Exact dispersion relations [ for 20 resonator (solid) and an infinite (dash-dot) CROWs.] 5

6. Tradeoffs Tradeoffs among delay, losses and bandwidth for a CROW consisting of 10 coupled ring resonators having a FSR of 310 GHz and propagation loss of 4 dB/cm 6

7. Experimental Process a) An optical micrograph of the CROW-MZI and an SEM zoom on the coupling region b) A theoretical fit (dashed) and a measurement (solid) of the CROW-MZI transmission. The fit parameters are κ=0.46 and loss of 30dB/cm c) A CROW consisting of 25 resonators 7

8. My suggestions 1 2 3 4 5 6 8

9. Challenges Are these geometric suggestions doable in software or later in fabrication? Design challenges Fabrication challenges Testing challenges Ideas for coupling 9

10. Example of ongoing research From Nanophotonics Lab. (Dr. Jacob Scheuer, Caltech)Nanophotonics Lab 10

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12. Suggestions / Questions ? Thanks you for you emails / comments ! 12

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