A. Wong-Foy

Integrated resonance-enhanced variable optical delay lines

A wide-tuning-range optical delay line is demonstrated in high (2%) index contrast waveguides. This device integrates four-stage ring resonator all-pass filters (APFs) with cascaded fixed spiral-type delay waveguides; each fixed delay path varies in length by a factor of two from the previous stage. A 2/spl times/2 switch separates each fixed delay and the tunable parts of the delay line. The APF allows for continuous delay tuning. This device enables coherent switching and continuous tuning ranges up to 2.56 ns.

Monolithic demodulator for 40-gb/s DQPSK using a star coupler

A novel device that demodulates both quadratures of the optical differential quadrature phase-shift keying (DQPSK) format in a single interferometer by using a 4 /spl times/ 4 star coupler was demonstrated. Simultaneous measurements of both DQPSK quadratures at 42.7 Gb/s are also presented.

Eight-wavelength add-drop filter with true reconfigurability

The authors demonstrate an integrated add-drop filter with true reconfigurability. It can drop any combination of eight wavelengths to any of eight drop ports, with less than 7 dB loss. Its features are suitable for mass production: use of standard silica waveguide technology, double-rejection switching and filtering for all paths, compactness, and power-efficient thermooptic switching.

Compact colorless tunable dispersion compensator with 1000-ps/nm tuning range for 40-gb/s data rates

A novel tunable dispersion compensator (TDC) with /spl plusmn/500-ps/nm tuning range and bandwidth support for 40-Gb/s signals is described. The TDC is constructed from a waveguide grating router (WGR) that provides very high spatial dispersion and a deformable cylindrical mirror for applying quadratic spatial phase across the dispersed wavefront. The WGRs 100-GHz free-spectral range (FSR) allows the device to simultaneously apply the same dispersion to all wavelength-division multiplexing (WDM) channels.

Bending of a planar lightwave circuit 2/spl times/2 coupler to desensitize it to wavelength, polarization, and fabrication changes

We present a planar lightwave circuit curved 2/spl times/2 coupler. Its splitting ratio has a low sensitivity to wavelength, polarization, and fabrication yet is low-loss and compact. We present simple formulae for its design. We demonstrate a 50/50 version in silica-on-silicon waveguides. We discuss the tradeoff between amplitude accuracy and phase accuracy in such densensitized couplers.

Colorless tunable optical dispersion compensator based on a silica arrayed-waveguide grating and a polymer thermooptic lens

We present a colorless tunable optical dispersion compensator (TODC) comprised of a silica arrayed-waveguide grating (AWG) directly coupled to a polymer thermooptic lens. Using silica for the AWG allows it to be low loss and manufactured by a standard process, and using polymer for the thermooptic lens allows it to have a large tuning range and low electrical power consumption. This hybrid TODC is fully solid-state and scales to a large figure-of-merit (dispersion range times bandwidth squared). We demonstrate a version with 100-GHz free-spectral range and 1300-ps/nm tuning range with a 3-dB bandwidth >39 GHz and a lens power consumption <74 mW

An integrated tunable chromatic dispersion compensator for 40 Gb/s NRZ and CSRZ

Periodic compensators using ring resonator allpass filters are demonstrated with tuning ranges up to 500 ps/nm and signal bandwidths of 45 to 60 GHz. System results are presented for 40 Gb/s NRZ and CSRZ.

Wavelength add-drop node using silica waveguide integration

We integrated a wavelength-selective cross-connect, de-interleaver, interleaver, power combiner, and variable attenuators on one silica waveguide chip and a band demultiplexer, band multiplexer, and optical monitor on another. These two chips are used to create an eight-channel add-drop node that is expandable up to 80 channels with minimal traffic interruption by adding more of these chips.

Planar lightwave circuit based reconfigurable optical add-drop multiplexer architectures and reusable subsystem module

We describe a wide range of reconfigurable optical add-drop multiplexer architecture designs that may be implemented in standard silica-on-silicon planar lightwave circuits. This proven, reliable technology offers high performance and cost-effective solutions for reducing complex service provisioning in reconfigurable optical networks. Recent advances enable very flexible wavelength routing devices for mesh- and ring-based networks to be implemented on a common subsystem integration platform. We show excellent system performance at 10 Gb/s.

Four-stage Mach-Zehnder-type tunable optical dispersion compensator with single-knob control

We present a concept for colorless tunable optical dispersion compensators consisting of a series arrangement of generalized interferometers and adjustable lenses. The designs require only one control knob to adjust the dispersion, making the control simple and low power. We demonstrate a four-stage all-two-arm version in silica waveguides that achieves 460-ps/nm tuning range on a 100-GHz grid for 40-Gb/s signals.