Digital optical switches for wavelength division multiplexing with extinction ratio exceeding 20 dB at both 1.3 μm and 1.5 μm

Photonic switching, when integrated with the optoelectronic circuit elements required for routing control and optical signal conditioning, is of interest for network reconfiguration, high-speed LANs, and optical cross-connects. The adiabatic modal evolution, asymmetric digital optical switch is a promising candidate for an efficient optical space switch for these applications. Its advantages include wavelength and polarization independent operation, complete switching for sufficient induced asymmetry, and since it is fabricated in a semiconductor, integration with other active devices. This switch is compact when fabricated with large opening angles and is suitable for application in WDM networks. We report on the fabrication and performance of the first InP digital optical switches with extinction ratios exceeding 20 dB at both 1.3 μm and 1.5 μm in the same switch for both polarizations