Coupled-mode theory and propagation losses in photonic crystal waveguides

University of Glasgow, Glasgow, Scotland, United Kingdom
Optics Express (Impact Factor: 3.49). 07/2003; 11(13):1490-6. DOI: 10.1364/OE.11.001490
Source: PubMed


Mode coupling phenomena, manifested by transmission "ministopbands", occur in two-dimensional photonic crystal channel waveguides. The huge difference in the group velocities of the coupled modes is a new feature with respect to the classical Bragg reflection occurring, e.g., in distributed feedback lasers. We show that an adequate ansatz of the classical coupled-mode theory remarkably well accounts for this new phenomenon. The fit of experimental transmission data from GaAs-based photonic crystal waveguides then leads to an accurate determination of the propagation losses of both fundamental and higher, low-group-velocity modes.

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Available from: C. Weisbuch, Jul 10, 2014
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