We show theoretically and with numerical simulations that the direction of the in-plane scattering from a subwavelength optical antenna system can be controlled by the frequency of the incident light. This optical steering effect does not rely on propagation phase shifts or diffraction but arises from phase shifts in the localized surface plasmon modes of the antenna. An analytical model is developed to optimize the parameters for the configuration, showing good agreement with a rigorous numerical simulation. The simulation predicts a 25° angular shift in the direction of the light scattered from two gold nanorods for a wavelength change of 12 nm.
© 2012 Optical Society of America
Original Manuscript: May 14, 2012
Revised Manuscript: July 27, 2012
Manuscript Accepted: August 31, 2012
Published: October 5, 2012
A. Djalalian-Assl, D. E. Gómez, A. Roberts, and T. J. Davis, "Frequency-dependent optical steering from subwavelength plasmonic structures," Opt. Lett. 37, 4206-4208 (2012)