Experimental evidence of modal properties using directional couplers in silicon-on-insulator

Autor: David J. Thomson, Seong Phun Chan, Graham T. Reed, Simon Howe, William R. Headley, Goran Z. Masanovic
Rok vydání: 2006
Předmět:
Zdroj: SPIE Proceedings.
ISSN: 0277-786X
DOI: 10.1117/12.652210
Popis: The single-mode optical rib waveguide is a fundamental building block for many, more complex optical circuits. Recent modelling has been provided in the literature that has investigated polarisation and modal properties of small, deeplyetched rib waveguides in SOI. In this paper we present work that has utilised a total of 160 directional couplers fabricated from rib waveguides of various waveguides dimensions, to investigate the validity of the published modelling. In particular 5 waveguide designs have been used to fabricate directional couplers of differing lengths, to map out the variation in coupling of power within the directional couplers. For a singlemode device, a characteristic sinusoidal variation is expected, but the sinusoid will be corrupted in the presence of higher order modes, each of which will have a different coupling length as compared to the fundamental mode. We have observed experimental results that are consistent with the modelling for each of the 5 waveguide designs, and hence we present experimental evidence of higher-order mode behaviour that is consistent with modelling.
Databáze: OpenAIRE