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Static performances and high-frequency characterisation of a GaInNAs/GaAs laser diode emitting at 1.35 μm are reported. Optimised molecular beam epitaxial (MBE) growth has allowed the achievement of a triple quantum well stack for improved dynamic properties. Broad area lasers exhibit a transparency current density of 642 A/cm2 at 20°C under pulsed operation and a characteristic temperature T0 of 80 K. Single-mode narrow-ridge waveguide devices emitting at 1.34 μm demonstrate a low threshold current of 26 mA under continuous wave (CW) operation at 25°C for an HR/as-cleaved cavity. The maximum output power reaches 9 mW with a slope efficiency of 0.13 W/A under CW operation. Intrinsic dynamic properties of the devices have been evaluated through relative intensity noise (RIN) measurements and small signal modulation. The dependence of the relaxation frequency on the bias current shows a slope of 0.92 GHz/mA1/2. The evolution of the damping factor against the squared relaxation frequency gives a K factor of 0.44 ns. RIN measurements yield a record relaxation frequency of 7.4 GHz for this triple-QW device. Small signal modulation shows a 3 dB bandwidth of 9.7 GHz for this new material system, compatible with 10-Gbit/s applications.

Optical pulses generated by an electroabsorption modulator are experimentally compressed in various negative-dispersion fibres. Theoretical and experimental pulsewidth evolutions are shown to be in excellent agreement when the voltage-dependent transmission and chirp functions are taken into account.

The variability of optical frequency modulation with electric field in an electro-optical phase section is analysed. When configured for maximum sensitivity, the electro-optical phase section was used to compensate for the chirp of the gain section: 48 ps and 8.5 GHz wide transform-limited pulses were obtained at 5 GHz.

Dynamic measurements of the Henry factor alpha H of InAs/GaAs Fabry-Perot lasers are compared for 3-, 5- and 10-QD layers. While alpha H dramatically increases with the bias current for 3- and 5-QD stacks, it only amounts to

High frequency characterisation of three-quantum well GaInNAs/GaAs lasers operating at 1.35 µm is reported. A relaxation frequency as high as 7.4 GHz and a 9.7 GHz small-signal bandwidth are demonstrated, indicating the potential for high bit rate (10 Gbit/s) direct modulation of these dilute nitrides on GaAs devices.

For short and medium reach network applications, a low-cost and high performance integrated laser-electroabsorption modulator source for 1.5 µm transmissions is proposed. Coolerless and isolator-free 10 Gbit/s transmission over 50 km, for temperature ranging from 10 to 80°C is demonstrated.

Small-signal frequency modulation response and chirp characteristics of a tunable, optically-pumped 1.6 µm vertical cavity surface emitting laser (VCSEL) based on microelectromechanical at wavelength tuning are presented for the first time. From the measurements the linewidth enhancement factor αH has been derived and is discussed.

High frequency FM sources are realised with a butt-jointed intracavity superlattice modulator in DBR lasers. They exhibit good lasing parameters and a 3 dB bandwidth up to 4 GHz is obtained with a modulated voltage control in the phase section.

A linewidth as narrow as 70 kHz together with a linewidth-power product of 0.2 MHz.mW have been achieved on 1450 mu m long compressively strained quantum well uniform DFB lasers. The results are achieved through a reduction of the phase-amplitude coupling factor, which is measured to be 1.7 times lower than in unstrained devices. >