We report the observation of nonlinearity-induced broadening of resonances in dynamically modulated directional couplers. When the refractive index of the guiding channels in the coupler is harmonically modulated along the propagation direction and is out-of-phase in two channels, coupling can be completely inhibited at resonant modulation frequencies. We observe that nonlinearity broadens such resonances and that localization can be achieved even in detuned systems at power levels well below those required in unmodulated couplers.
© 2009 Optical Society of America
Original Manuscript: March 30, 2009
Manuscript Accepted: July 21, 2009
Published: September 4, 2009
A. Szameit, Y. V. Kartashov, M. Heinrich, F. Dreisow, R. Keil, S. Nolte, A. Tünnermann, V. A. Vysloukh, F. Lederer, and L. Torner, "Nonlinearity-induced broadening of resonances in dynamically modulated couplers," Opt. Lett. 34, 2700-2702 (2009)