摘要 |
A compact monolithic Mach-Zehnder switch is formed such that one of the waveguide paths (69, 70) between the input and output couplers (67, 68) contains a material which exhibits a resonant nonlinearity, whereby its refractive index changes when pump power propagates through it. Each of the waveguide paths (69, 70) has a different propagation constant whereby signal light is subjected to a different delay in each path when no pump power is propagating through the rare nonlinear path. An input signal applied to the input (71, 72) of the switch appears at a first output terminal (73, 74) when the pump power does not propagate through the nonlinear path, and it appears at a second output terminal (73, 74) when the pump power is applied to the nonlinear path. Switching occurs at relatively low levels of pump power. |