Abstract
We numerically simulate the propagation and switching of ultra-short
pulses in a metamaterial nonlinear directional asymmetric coupler where
one of the guides is a conventional medium with a positive refraction
index having a decreasing Kerr nonlinearity. The second guide is based
in a metamaterial. A complete study of the nonlinear dynamics of
ultra-short pulses propagation and switching in this new nonlinear
directional coupler, including the transmission characteristics,
bistability, critical power, compression factor and extinction
coefficients are presented and compared to those of a conventional
coupler. We conclude that the conventional coupler has higher
transmission efficiency and extinction rate when compared with the
metamaterial coupler. However the metamaterial coupler presents
bistability which opens the possibility of such device to be used in a
large variety of optical switching, storage and logical gates. We show
that the input power range leading to bistability can be optimized by
controlling the profile of the nonlinear refraction index of the
conventional channel. (C) 2012 Elsevier B.V. All rights reserved.
Users
Please
log in to take part in the discussion (add own reviews or comments).