Components for silicon plasmonic nanocircuits based on horizontal Cu-SiO2-Si-SiO2-Cu nanoplasmonic waveguides

Institute of Microelectronics, A STAR (Agency for Science, Technology and Research), 11 Science Park Road, Science Park-II, Singapore 117685, Singapore.
Optics Express (Impact Factor: 3.49). 03/2012; 20(6):5867-81. DOI: 10.1364/OE.20.005867
Source: PubMed

ABSTRACT We report systematic results on the development of horizontal Cu-SiO₂-Si-SiO₂-Cu nanoplasmonic waveguide components operating at 1550-nm telecom wavelengths, including straight waveguides, sharp 90° bends, power splitters, and Mach-Zehnder interferometers (MZIs). Owing to the relatively low loss for propagating (~0.3 dB/µm) and for 90° sharply bending (~0.73 dB/turn), various ultracompact power splitters and MZIs are experimentally realized on a silicon-on-insulator (SOI) platform using standard CMOS technology. The demonstrated splitters exhibit a relatively low excess loss and the MZIs exhibit good performance such as high extinction ratio of ~18 dB and low normalized insertion loss of ~1.7 dB. The experimental results of these devices agree well with those predicted from numerical simulations with suitable Cu permittivity data.

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