Parallel-coupled dual racetrack silicon micro-resonators for quadrature amplitude modulation

Department of Electrical and Computer Engineering, Rutgers University, Piscataway, NJ 08854, USA.
Optics Express (Impact Factor: 3.49). 08/2011; 19(16):14892-902. DOI: 10.1364/OE.19.014892
Source: PubMed


A parallel-coupled dual racetrack silicon micro-resonator structure is proposed and analyzed for M-ary quadrature amplitude modulation. The over-coupled, critically coupled, and under-coupled scenarios are systematically studied. Simulations indicate that only the over-coupled structures can generate arbitrary M-ary quadrature signals. Analytic study shows that the large dynamic range of amplitude and phase of a modulated over-coupled structure stems from the strong cross-coupling between two resonators, which can be understood through a delicate balance between the direct sum and the "interaction" terms. Potential asymmetries in the coupling constants and quality factors of the resonators are systematically studied. Compensations for these asymmetries by phase adjustment are shown feasible.

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Available from: Ryan A Integlia, Aug 24, 2014
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    • "In section VI, we have carried out tunability study of off-axis MRR and found that off-axis ring can pave the way for more compact modulator in comparison to the SOI modulator based on the conventional MRR [16], [17]. This might be suitable for high density on-chip photonic applications as it has high Q-factor with resonant notches which are very sensitive to the effective refractive index and radius of the off-axis inner ring. "
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