Rg Ronald Broeke

A compact digitally tunable seven-channel ring laser

A seven-channel ring laser was realized by monolithic integration of a compact 4/spl times/4 PHASAR (de)multiplexer with four amplifiers in InP. The PHASAR was fabricated using a double-etch technique, enabling a total size of the ring laser of only 1/spl times/1.5 mm/sup 2/. Light was coupled out via the outer array waveguides. Reflections are minimized by using mode filters and angled facets. Threshold-currents of 70 mA and a sidemode suppression ratio of 40 dB were measured. In principle, a ring laser with N amplifiers can produce 3N-3 different wavelengths.

An integrated 4 x 4-channel multiwavelength laser on InP

We present a compact 16-channel digitally tunable laser integrated on InP with the possibility to produce groups of four wavelengths at the same time. The cavity contains two arrays of four semiconductor optical amplifiers (SOAs) with two periodical four-channel intracavity phased arrays (PHASARs) with channel spacings of 100 and 400 GHz. By activating two out of the eight SOAs, 16 different wavelengths can be selected. Light was coupled out of the cavity by waveguides placed in the second focal order of the PHASARs. Reflections from the end facets of the wafer are minimized using mode filters and angled output waveguides.

An integrated coupled-cavity 16-wavelength digitally tunable laser

We present a digitally tunable laser that was realized by coupling two wavelength periodical four-channel lasers. The lasers were coupled with a multimode interference coupler, in such a way that the device has a common intracavity output waveguide containing the full multiplexed signal. In the two laser cavities, 1 /spl times/ 4 PHASARs were used with a channel spacing of 100 and 400 GHz, respectively. By coupling each PHASAR to four semiconductor optical amplifiers, 4 /spl times/ 4 channels were generated. The measured SMSR for each of the 16 wavelengths is better than 40 dB.

A wavelength converter with integrated tunable laser

An interferometric wavelength converter has been monolithically integrated with a digitally tunable 4-channel laser. Conversion to all laser channels has been demonstrated and excellent static extinction ratios of over 20 dB have been observed. An extinction ratio improvement of 13 dB has been measured.

AWG-Based Monolithic

We report a novel arrayed waveguide grating (AWG)-based 4 × 12 GHz multichannel harmonically modelocked semiconductor laser operating near 1535 nm, which was realized by monolithically integrating a semiconductor optical amplifier (SOA) array, a set of passive optical delay lines, an AWG with 400 GHz channel spacing, a saturable absorber, and a common output SOA. Our device layout and fabrication were completed on the European JePPIX InP photonic integration platform, based on the multiproject wafer run foundry approach. We demonstrated four wavelength channels operating in the fifth harmonic mode-locking regime. Channel repetition rate of 12 GHz and 3-dB RF linewidth as narrow as 6 kHz were obtained. The exhibited performance makes our device a very promising candidate as an ultracompact multichannel light source for future hybrid optical time and wavelength division multiplexing, high-speed photonic analog-to-digital conversion, and optical clock recovery applications.

4 \times 12

Comparison of optical bandwidth of a SOA-MZI using 1x2 input couplers to one with 2x2 input couplers is presented. The simulation shows that wider bandwidth can be obtained in case where 2x2 couplers are used.

GHz Multichannel Harmonically Mode-Locked Laser

We presented the first integrated WDM ring laser. It operates CW at three adjacent wavelengths spaced by 3.2 nm. Lowest threshold currents are 70 mA and the SMSR is 30 dB when both the common and the selected SOA are operated at 100 mA.. One of the channels was not lasing because of a defect amplifier. The small size of the device (1.5 /spl times/ 3 mm/sup 2/) demonstrates the potential of compact technology.

Optical bandwidth of Mach-Zehnder interferometer wavelength converters

An apparatus for determining the direction of ambient airflow and a method for the use thereof. The apparatus includes man-made or natural fibers that float when released into the air by a user. The direction of ambient airflow is determined by observing the direction of movement of the fibers from the point of release from the users hand.

A dual-phasar multi-wavelength ring laser

A 1x16 AWG with an 87 nm Free Spectral Range is integrated with an array of photo detectors and used to detect picometer wavelength variations of a coherent light source.

An all-optical wavelength converter in a layer-stack suitable for compact photonic integration

We present a digitally tunable laser that was realized by coupling two wavelength periodical four-channel lasers. The lasers were coupled with a multimode interference coupler, in such a way that the device has a common intracavity output waveguide containing the full multiplexed signal. In the two laser cavities, 1 /spl times/ 4 PHASARs were used with a channel spacing of 100 and 400 GHz, respectively. By coupling each PHASAR to four semiconductor optical amplifiers, 4 /spl times/ 4 channels were generated. The measured SMSR for each of the 16 wavelengths is better than 40 dB.