F. Poingt

High Bandwidth Operation of Directly Modulated Laser Based on Quantum-Dash InAs–InP Material at 1.55

The modulation bandwidth has been identified as a specific limitation of quantum-dot or quantum-dash (QDash) lasers for direct modulation application. Solutions using tunnel injection and p-doping have already been demonstrated to increase the modulation bandwidth above 10 GHz, but with complex tunnel injection design and p-doping induced high internal losses. We show in this letter that the use of optimized QDashes and waveguide structure is sufficient to reach such high bandwidth at 1.55 mum. The device is validated by a large signal modulation demonstration at 10 Gb/s.

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We propose and demonstrate asymmetric 10 Gbit/s upstream--100 Gbit/s downstream per wavelength colorless WDM/TDM PON using a novel hybrid-silicon chip integrating two tunable lasers. The first laser is directly modulated in burst mode for upstream transmission over up to 25 km of standard single mode fiber and error free transmission over 4 channels across the C-band is demonstrated. The second tunable laser is successfully used as local oscillator in a coherent receiver across the C-band simultaneously operating with the presence of 80 downstream co-channels.

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This letter reports on a hybrid III–V on silicon arrayed waveguide grating laser, fabricated by a wafer bonding technique. The III–V materials provide the optical gain for the laser while an arrayed waveguide grating and Bragg reflectors on silicon on insulator complete the cavity for single mode selection and laser feedback. The laser shows a threshold current <formula formulatype=inline> <tex Notation=TeX>

Directly modulated and fully tunable hybrid silicon lasers for future generation of coherent colorless ONU

{sim}{rm 40}~{rm mA}

Wavelength Selectable Hybrid III–V/Si Laser Fabricated by Wafer Bonding

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Integrated hybrid III–V/Si laser and transmitter

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An analysis of 1.55μm InAs∕InP quantum dash lasers

</tex></formula>. Independent lasing of five wavelength channels spaced by 392 GHz is demonstrated.

Distributed feedback-like laser emission in photonic crystal waveguides on InP substrate

This paper reports on recent advances on integrated hybrid InP/SOI lasers and transmitters. Based on a molecular wafer bonding technique, we develop hybrid III-V/Si lasers exhibiting new features: narrow III-V waveguide width of less than 3 μm, tapered III-V and silicon waveguides for mode transfer. These new features lead to good laser performances: a lasing threshold as low as 30mA and an output power of more than 10 mW at room temperature in continuous wave operation regime from a single facet. Continuous wave lasing up to 70°C is obtained. Moreover, hybrid III-V/Si lasers, integrating two intra-cavity ring resonators, are fabricated. Such lasers achieve a thermal tuning range of 45 nm, with a side mode suppression ratio higher than 40 dB. More recently we demonstrate a tunable transmitter, integrating a hybrid III-V/Si laser fabricated by wafer bonding and a silicon Mach-Zehnder modulator. The integrated transmitter exhibits 9 nm wavelength tunability by heating an intra-cavity ring resonator, high extinction ratio from 6 to 10 dB, and excellent bit-error-rate performance at 10 Gb/s.

Effect of P-doping on temperature and dynamic performances of 1550nm InAs/InP Quantum Dash based lasers

Calculations show that electron states are not confined in the dashes in 1.55μm InAs∕InP quantum dash-in-a-well laser structures. The combination of strain and three-dimensional confinement reduces the calculated density of states (DOS) near the valence band maximum, with the conduction and valence DOS then almost equal close to the band edges. Calculations and photoabsorption measurements show strongly polarized spontaneous emission and gain spectra. Experimental analysis shows the room temperature threshold current is dominated by nonradiative current paths.

Evidence of gain modulation in km-long lasers

Lasing of triangular and square lattice photonic crystal, waveguides on InP substrate is investigated around the 1.5-/spl mu/m wavelength by optical pumping. The lattice period of the fabricated structures is varied over a very large scale, thereby allowing a detailed exploration of the laser behaviors in the cases of micrometer width waveguides. A genuine distributed feedback (DFB) laser emission is observed in the gap for W2-3 waveguides in the /spl Gamma/M direction of a triangular lattice. A different behavior is obtained for W3 waveguides in the /spl Gamma/K direction of the same lattice as well as for W1 and W3 waveguides in the /spl Gamma/X direction of a square lattice. The laser emission is found to occur at the /spl Gamma/ point of the Brillouin zone (wavevector k=0) when the emission frequency is outside the gap. The DFB-like laser emission is intrinsically single mode in this case. Plane wave calculations show that the field distributions of the two DFB components are radically different. The emitting mode is well localized in the guide core while the non-lasing mode spreads over the whole crystal.