We propose and theoretically verify an efficient mechanism of broadband coupling between incident light and on-chip dielectric slot waveguide by employing a tapered plasmonic nanoantenna. The nanoantenna receives free space radiation and couples it to a dielectric slot waveguide with the efficiency of up to 20% in a broad spectral range, having a small footprint as compared with the currently used narrowband dielectric grating couplers. We argue that the frequency selective properties of such nanoantennas also allow for using them as ultrasmall on-chip multiplexer/demultiplexer devices.
© 2013 Optical Society of America
Original Manuscript: June 28, 2013
Revised Manuscript: October 14, 2013
Manuscript Accepted: October 16, 2013
Published: November 14, 2013
I. S. Maksymov and Yu. S. Kivshar, "Broadband light coupling to dielectric slot waveguides with tapered plasmonic nanoantennas," Opt. Lett. 38, 4853-4856 (2013)