Download Coupled Resonator Optical Waveguides (CROWs) Fatemeh Soltani

Coupled Resonator Optical Waveguides (CROWs)
Fatemeh Soltani, McGill University, Montreal
[email protected]
Montivation:
CROW can be combined of different type of resonators coupled to each other such as ring resonators and FabryPerot. These coupled waveguides can make a new type of resonating waveguide with much more flexibility to use in
optical layouts. Engineering the properties of CROW is more convenient and ultra-slow group velocities brings
some new applications for delay lines, optical memories and in all-optical switching. As part of my PHD project I
am focused on use of polymer materials in optical switching, so as the measurement of a CROW interferometer
realized in polymer material, it can give me some directions toward my project.
Figure 1: An Illustration of CROW [1]
Also propagation of light in a CROW can be analyzed and different properties like loss in rings are testable.
Figure 2: Travelling wave in a finite CROW [1]
Analytical characterization:
Dispersion relations can be improved by higher number of ring resonators. It has been shown in graph below:
Figure 3: Exact dispersion relations
There is a good trade-off between delay and bandwidth of CROWS. For more number of CROWs the higher the
transmission the lower the delay. This will cause use of higher bandwidth.
Figure 4: Tradeoff of CROWs [1]
My Suggestion for design:
I would like to work on different combination of CROWs with different geometries and different combinations such
as below:
Figure 5: Different designs
Design Challenges:
As I get feedbacks, CROWs are sensitive to fabrication. So I may consider to use disks instead of ring due to lower
loss. Having ellipse in design may be good but it will have slightly higher loss. I am planning to make different
variation of rings or disks as 1, 2, 3, 5, 10, 20, 50. Packing methods also need to be considered.
References:
[1] 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
[2] Michael L. Cooper et. al, “Quantitative infrared imaging of silicon-oninsulator microring resonators”, Optics Letters / Vol.
35, No. 5 / March 1, 2010