HIGH-INPUT-POWER SATURATION PROPERTIES OF A POLARIZATION-INSENSITIVE SEMICONDUCTOR MACH-ZEHNDER INTERFEROMETER GATE SWITCH FOR WDM APPLICATIONS

We propose that a polarization-insensitive Mach-Zehnder interferometer (MZI) switch is useful for optical gate elements, especially if multi wavelength signals are input, This device has high-input-power saturat ion properties, which shows that both the operating voltage and the ex tinction ratio do not change when the optical input power reaches at l east +18 dBm, A high extinction ratio of 30 dB was achieved in the wid e-wavelength range of 20 nm, Moreover, the extinction ratio can be imp roved by up to 45 dB by using a cascaded configuration to decrease cro sstalk, These results indicate the MZI gate switch is well suited to w avelength-division multiplexing (WDM) network components.