Photothermal switching of SOI-waveguide-based Mach-Zehnder interferometer with integrated plasmonic nanoheater
2014 (English)In: Plasmonics, ISSN ISSN: 1557-1963, Vol. 9, no 5, 1197-1205 p.Article in journal (Refereed) Published
We theoretically and numerically investigate photothermal switching of a Mach-Zehnder interferometer (MZI) based on two Si waveguides integrated with plasmonic nanoheater. The nanoheater is a composite nanowire with Au/Al2O3/Au three-layer structure, which is designed to have a high-efficient optical absorption peak at wavelength of 1064 nm. Based on this finding, we further analyze a MZI built with two 40 μm-long symmetric waveguide branches, each integrated with a 20 μm-long nanoheater. The optical switching power of the MZI device is 190 mW (280 mW) for the capped (buried) channel waveguide, when pumped by a circular Gaussian beam with a waist of 10 μm. Alternatively, the switching power can be reduced to 38 mW (56 mW) by using an astigmatic Gaussian beam, with a semi-major axis of 10 μm and an aspect ratio of 5. The switching response time of the MZI is 0.7 μs (1.0 μs) for capped (buried) channel waveguide design. Our design opens a new route for optically driven non-contact optical on-off switching with sub-microsecond time response.
Place, publisher, year, edition, pages
Springer, 2014. Vol. 9, no 5, 1197-1205 p.
Atom and Molecular Physics and Optics
Research subject Physics
IdentifiersURN: urn:nbn:se:kth:diva-143674DOI: 10.1007/s11468-014-9731-2ISI: 000341841500026ScopusID: 2-s2.0-84901514254OAI: oai:DiVA.org:kth-143674DiVA: diva2:708244
FunderSwedish Foundation for Strategic Research Swedish Research Council
Updated from "Accepted" to "Published". QC 201410132014-03-272014-03-272014-10-13Bibliographically approved