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

Record polarization-independent extinction ratios are reported for ridge waveguide digital optical switches in InP/InGaAsP. Wavelength insensitivity is demonstrated for the first time, with extinction ratios that exceed 20 dB at both 1.3 and 1.5 mum for the same switch. The switch's total opening angle of 0.5-degrees is more than a factor of two larger than other digital optical switches demonstrated at any wavelength.

Photonic switching is of interest for network reconfiguration, high-speed LANs, and optical cross connects.1-3 The adiabatic- modal-evolution, asymmetric digital optical switch (DOS) is a promising candidate for these applications. It can operate independent of light polarization, it is less sensitive to wavelength and fabrication uncertainties than are conventional directional couplers, it switches completely for sufficient induced asymmetry, and because it is a semiconductor, it may be integrated with other active devices. But for the DOS to achieve this potential, two deficiencies must be overcome. Its size must be reduced by increasing the opening angle, and to allow for cascading of switches, high extinction ratios must be achieved.

Photonic switching, when integrated with the optoelectronic circuit elements required for routing control and optical signal conditioning, is of interest for network reconfiguration, highspeed LANs, and optical cross-connects [l]-[4]. The adiabatic modal evolution, asymmetric Digital Optical Switch is a promising candidate for an efficient optical space switch for these applications. It can operate independently of light polarization, it is less sensitive to wavelength and fabrication uncertainties than conventional directional couplers, it switches completely for sufficient induced asymmetry, and because it is a semiconductor it may be integrated with other active devices.

In this paper, we demonstrate record performance of a 0.5° angle InP/InGaAsP digital optical switch (DOS) at 1.3 μm wavelength. Extinction ratios of 30 dB at an injection current of 50 mA have been achieved, almost 10 dB higher than any previous report. We have also measured an extinction ratio of 20 dB at 30 mA, a reduction of more than 40% in injection current from our previous results. Propagation losses of these waveguides are also reported

In this paper, we demonstrate record performance of a 0.5/spl deg/ angle InP/InGaAsP digital optical switch (DOS) at 1.3 /spl mu/m wavelength. Extinction ratios of 30 dB at an injection current of 50 mA have been achieved, almost 10 dB higher than any previous report. We have also measured an extinction ratio of 20 dB at 30 mA, a reduction of more than 40% in injection current from our previous results. Propagation losses of these waveguides are also reported. >