Authors:	J. Van Campenhout, P. Rojo Romeo, D. Van Thourhout, C. Seassal, P. Regreny, L. Di Cioccio, J.M. Fedeli, R. Baets
Title:	Design and optimizations of electrically injected InP-based microdisk lasers integrated on and coupled to a SOI waveguide circuit
Format:	International Journal
Publication date:	1/2008
Journal/Conference/Book:	Journal of Lightwave Technology
Volume(Issue):	26(1) p.52-63
DOI:	10.1109/jlt.2007.912107
Citations:	43 (Dimensions.ai - last update: 17/11/2024) 34 (OpenCitations - last update: 3/5/2024) Look up on Google Scholar
Download:	(1.4MB)

Abstract

We have performed a numerical study involving the
design and optimization of InP-based microdisk lasers integrated
on and coupled to a nanophotonic silicon-on-insulator (SOI) waveguide
circuit, fabricated through bonding technology. The theoretical
model was tested by fitting it to the lasing characteristics
obtained for fabricated devices, which we presented previously.
A good fit was obtained using parameter values that are consistent
with numerical simulation. To obtain optimized laser performance,
the composition of the InP-based epitaxial layer structure
was optimized to minimize internal optical loss for a structure compatible
with efficient current injection. Specific attention was paid
to a tunnel-junction based approach. Bending loss was quantified
to estimate the minimum microdisk diameter. The coupling between
the InP microdisk and Si waveguide was calculated as function
of the bonding layer thickness, waveguide offset and waveguide
width. To study the lateral injection efficiency, an equivalent
electrical network was solved and the voltage-current characteristic
was calculated. Based on these results, the dominant device
parameters were identified, including microdisk thickness and radius,
coupling loss and tunnel-junction p-type doping. These parameters
were optimized to obtain maximum wall-plug efficiency,
for output powers in the range 1–100 W. The results of this optimization
illustrate the potential for substantial improvement in
laser performance.