Reflection properties of coupled-ring reflectors

• Published in: Journal of lightwave technology Vol. 24; no. 4; pp. 1865 - 1874
• Main Authors: Chung, Y., Doo-Gun Kim, Dagli, N.
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.04.2006; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Applied sciences; Circuit properties; Couplers; Detection, estimation, filtering, equalization, prediction; Diode lasers; Electric, optical and optoelectronic circuits; Electronics; Exact sciences and technology; Forming; Fundamental areas of phenomenology (including applications); Guidelines; Information, signal and communications theory; Insertion loss; Integrated optics; Integrated optics. Optical fibers and wave guides; Joining; Laser diodes; Laser optical systems: design and operation; Lossless; Optical and optoelectronic circuits; Optical coupling; Optical propagation; Optical reflection; Optics; Physics; Propagation losses; Reflection; Reflectors; Resonators, cavities, amplifiers, arrays, and rings; ring resonators; Shape; Signal and communications theory; Signal, noise; Systems, networks and services of telecommunications; Telecommunications; Telecommunications and information theory; Transmission and modulation (techniques and equipments); Transmission line matrix methods; tunable filters; Integrated optics; tunable filters; Lossless circuit; Multivariable control; Diode; Reflector; Data transmission; Bus(channel); Waveguide; Single mode laser; Reflection spectrum; Ring resonator; Interconnection; ring resonators; Tunable filter; Integrated circuit; Insertion loss; Transfer matrix method; Coupling factor; Transmission loss
• ISSN: 0733-8724; 1558-2213
• DOI: 10.1109/JLT.2006.871021

The reflection properties of a coupled-ring reflector (CRR) are analyzed using the transfer matrix method. The CRR is composed of two coupled rings that are coupled to a bus waveguide. Depending on the combination of the cross-coupling ratios of the couplers, the reflection spectrum shape changes greatly. In the lossless case, the reflection spectrum has four peaks when the ring-bus coupling ratio is small. When the ring-bus coupling ratio is more than half and the ring-ring coupling is very small, the four peaks broaden, forming a single peak with still considerably narrow reflection spectrum, which makes the CRR attractive in applications requiring compact reflectors such as for single-mode laser diodes. The dependence of the propagation and insertion losses of the couplers on the reflection spectrum is also investigated, and the design guidelines are presented.