Abstract
Ultracompact directional couplers (DCs) based on dielectric-loaded surface
plasmon-polariton waveguides (DLSPPWs) are analyzed using the effective index method
(EIM), with the coupling, both in the parallel interaction region and in- and
out-coupling regions, being taken into account. Near-field characterization of
fabricated DCs performed with a scanning near-field optical microscope verifies the
applicability of the EIM in the analysis and design of DLSPPW-based wavelength-selective
DCs. The design approach applicable to a large variety of integrated optical waveguides
is developed, enabling the realization of DCs in which optical signals at two different
wavelengths are coupled into two separate output channels. The developed approach
ensures minimization of the crosstalk and overall DC length via simultaneous adjustment
of the waveguide separation and length of the interaction region. As an example, the
design of a DLSPPW-based DC for complete separation of telecommunication signals at the
wavelengths $\lambda=1400$ nm and $\lambda=1600$ nm between two output channels
separated by 6 $\mu$m is worked out, resulting in the total device length of 52.3
$\mu$m. In addition, the design of an ultracompact DLSPPW-based DC waveguide crossing
that ensures a very low crosstalk over a large wavelength band in the telecommunication
range is considered.
© 2009 IEEE
PDF Article
More Like This
Cited By
You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.
Contact your librarian or system administrator
or
Login to access Optica Member Subscription