R. Varrazza

Ultra-low crosstalk, compact integrated optical crosspoint space switch arrays employing active InGaAsP-InP vertical waveguide couplers

An optical crosspoint switch array based on vertical waveguide couplers are experimentally demonstrated to have very low on-chip crosstalk level of <-60 dB and a ON-OFF contrast of >50 dB. The structure is also compact (250/spl times/250 /spl mu/m per input/output pair) and easily scalable.

All-optical switching in a vertical coupler space switch employing photocarrier-induced nonlinearity

Summary form only given. Nonlinear optical switches will be key devices in order to realize all-optical signal processing in order to meet increasing data speed requirements in future optical communications systems. Of various nonlinear optical effects, the photocarrier-induced band edge nonlinearity in semiconductor quantum wells has relatively large amplitude with a time constant in the 10-ps range depending on the carrier sweep-out time. It has been shown theoretically that a device based on such an effect and a vertical coupler structure can make an effective nonlinear optical switch. In the paper a new form of all-optical switch employing photocarrier-induced nonlinearity based on a vertical coupler structure, which allows high switch contrast, is reported.

Effect of nitrogen on the temperature induced wavelength shift of GaInNAs lasers

The temperature dependence of the lasing wavelength of GaInNAs quantum well laser is found to be 0.394 nm/K, which is smaller than conventional InGaAsP material system. The band anticrossing model is utilised to derive an understanding of this effect.

Low power electrochromic variable optical attenuator with 50dB attenuation range

A variable optical attenuator based upon a new molybdenum electrochromic compound is described. The device exhibits an attenuation range of >50dB at 1310nm, for a drive power of 150/spl mu/W, and an insertion loss of 1.5dB.

High speed, ultralow crosstalk integrated optical crosspoint switch array employing vertical waveguide couplers

An optical crosspoint switch array based on vertically coupled waveguides is experimentally demonstrated with switching time of <1.5 nanoseconds. An on-chip crosstalk level of 60 dB and a ON-OFF contrast of greater than 50 dB have been measured.