Satoshi Suda

Optical Nonlinear-Effect Compensator Based on Vertical-cavity Saturable Absorber

We demonstrate an optical nonlinear-effect compensator based on InGaAIAs/InP vertical-cavity saturable absorber. A large negative nonlinear phase-shift was observed both in modelling and experiments, which will be useful for compensating fiber nonlinearities in optical domain.

Optical nonlinear phase shifter using vertical microcavity with saturable absorber

We propose an optical nonlinear phase-shifter based on resonant cavity saturable absorber. A large nonlinear phase-shift was observed in both modeling and experiment. The device would be useful for mitigating fiber nonlinearities in optical domain.

High speed response of nonlinear optical phase-shifter based on vertical micro-cavity saturable absorber

We present the modeling and experiment on the intensity-dependent phase shift of a nonlinear optical phase-shifter based on vertical micro-cavity saturable absorber for high-speed response. We demonstrated the 25ps transient response with a large negative nonlinear phase shift of over -0.7 radian. Our device would enable us to control the phase of high speed optical pulses including the compensation of fiber nonlinear effects in optical domain.

Optical-Time-Division Demultiplexing of 172 Gb/s to 43 Gb/s in a-Si:H Waveguides

We demonstrate optical-time-division demultiplexing of 172-43 Gb/s based on degenerate four-wave mixing in a 17-mm-long hydrogenated amorphous silicon (a-Si:H) wire waveguide. The a-Si:H wire waveguide has a record-low propagation loss of 1.0 dB/cm and a low two-photon-absorption loss of 0.2 cm/GW, and the nonlinear figure of merit is estimated to be 0.97, which is more than twice as effective as conventional crystalline silicon wire waveguides. We achieved successful error-free demultiplexing with an ON/OFF conversion efficiency of -10 dB and a power penalty of only 1.1 dB at a bit error rate of 10-9. No optical damage to the a-Si:H waveguide was observed even after a continuous pump injection at an average power of several tens of mW for a couple of hours.

Tunable Optical Delay and Nonlinear Phase Shift using 1.55 μm VCSEL

We present the tunable optical delay and nonlinear phase-shift using reverse-biased 1.55 mum VCSEL. The reduction of recovery time in saturable absorber with increasing reverse bias would enable to control the phase of high speed optical signals

Characterization of Spot-Size Dependence of Coarse Wavelength Division Multiplexing Dielectric Multilayer Thin-Film Filters for Planner Lightwave Circuit Platforms

We present the first measurement and modeling on the spot-size dependence multilayer thin-film filters used in coarse wavelength division multiplexing (CWDM) systems. The noticeable spot-size dependence can be seen for use in their multiplexer/demultiplexer based on planner lightwave circuit (PLC) platforms.

Tunable optical equalizer based on 1.55 μm VCSEL for modulation bandwidth enhancement

We propose and demonstrate the tunable optical equalization function using a 1.55 mum VCSEL biased below threshold. Bandwidth enhancement can be tuned by bias current. A modulation bandwidth beyond 70 GHz was obtained on LiNbO3 modulators.

Optical compensation of fiber nonlinearity using vertical micro-cavity saturable absorber

We demonstrate the optical compensation of self-phase modulation in fiber by using the VCSEL-based nonlinear phase shifter. The transient phase shift of 25psec pulses induced by self-phase modulation in fiber could be optically compensated.

Optical phase shifter based on VCSEL and slow light waveguide

We present the manipulation of optical phase using a VCSEL-based nonlinear phase shifter and a Bragg reflector slow light waveguide. We demonstrate the optical compensation of self-phase modulation in fiber by using the VCSEL-based nonlinear phase shifter. The transient phase shift of 25 psec pulses induced by self-phase modulation in fiber could be optically compensated.

Nanoimprint and nano-machining process for tunable hollow waveguide devices

We present the fabrication of circular grating based on nanoimprint and nano-machining process. We successfully demonstrate the nanoimprint of circular grating with pitch of 780 nm for large-area tunable hollow waveguide devices.