The power imbalance between different waveguide outputs is compensated by manipulating the dispersion of the guided propagation in the multimode interference (MMI) region. This is attainable using a tapered region at the beginning of the MMI region that has been verified through simulation and experiment. From this, the fabrication tolerance for the diameters of holes in a tapered 1×3 photonic crystal waveguide (PhCW) splitter is relaxed up to a range of at least 27 nm. The output power is well-balanced to within 1 dB. The effective bandwidth of the splitters shifts only around 13 nm, for a reduction of 10 nm in the diameter of the PhCW holes. The optimized component is an outstanding ultracompact 1×3 splitter for the photonic integrated circuit (PIC).
© 2011 Optical Society of America
Original Manuscript: April 28, 2011
Revised Manuscript: June 14, 2011
Manuscript Accepted: July 8, 2011
Published: August 8, 2011
Min Zhang, Asger Christian Krüger, Nathaniel Groothoff, Thomas Balle, and Martin Kristensen, "Relaxed fabrication tolerance for self-imaging photonic crystal waveguide splitters using a tapered multimode interference region," Opt. Lett. 36, 3058-3060 (2011)