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The design, fabrication and testing of 1550 nm DFB lasers with monolithically integrated electroabsorption modulators are reported. System performance of butterfly-packaged devices in 10 Gbit/s NRZ transmission over standard single mode fibre (SMF) with 17 ps/nm/km dispersion is included. Among the results are l0 Gbit/s transmission without the aid of optical amplifiers up to the theoretical limit of 50 km and up to 150 km using one optical booster amplifier.

We have developed a new layer stack based on the integration of active and passive devices in InGaAsP/InP using an MOVPE re-growth technique. The high quality of the new stack is shown by the performance of an all-optical wavelength converter. The converted wavelength showed a static extinction ratio of 33 dB and a − 1.5 dB power penalty in 2.5 Gb/s BER measurements. No error floor was detected.

The sign of the strain in a multiquantum well (MQW) active layer of an InGaAs/InP laser determines whether lasing occurs from the electron–heavy hole transition or from the electron‐light hole transition. Lasing from the electron‐light hole transition is reported to provide a much better performance than predicted by theory. It is concluded that this gives the best device performance, providing a higher differential gain, a lower threshold current, a record low linewidth enhancement factor of 1.5, and a K factor of 0.22 ns, potentially allowing a 3 dB modulation bandwidth of 40 GHz.

This paper describes the design, fabrication, and testing of transmitter modules for repeaterless long haul transmission of 10 Gbit/s non-return-to-zero (NRZ) data over standard single mode fibre, with a dispersion of 17 ps/km/nm and an attenuation of 0.2 dB/km at a wavelength of 1.554 nm.

Information on interfacial mass transport of cadmium in cadmium sulfide suspensions and er equilibrium conditions has been obtained by probing with a radiotracer for cadmium. The transport of Cd2+ ions from the cadmium sulfide solid particles to the saturated solution and visa versa is followed by adding radioactive 109Cd2+ to the solution and measuring the amount of radioactivity present in the solution as a function of time. The amount of exchangeable cadmium in or at the solid/liquid interface, which is deduced from the final value of radioactivity in the solution appeared to be 1.8 to 2.3 times the amount of cadmium in one lattice layer. Compartmental analysis of the experimental data revealed that 4 different cadmium species are involved in the exchange processes, one of which being the cadmium in the bulk of the solution, and another one, representing 40% to 50 of one lattice layer, which exchanges rapidly with the solution in comparison with the other two species left.