Optically controlled contradirectional coupler

A multiple-quantum-well optically controlled contradirectional coupler has been realized following the design criteria discussed here and elucidated by the simulations. Our room-temperature experiments show a power-dependent contradirectional coupling condition, allowing optically controlled switching between two output channels with control energies on the order of 1 pJ, and at a wavelength around 1.55 /spl mu/m. The device is treated theoretically by a coupled mode analysis in order to compute the linear and nonlinear transmission spectra at the two output ports. The effects induced by the propagation of intense control beams are modeled using a nonlinear two-dimensional beam propagation method.