A direct measurement of electron and hole leakage in InGaAsP/InP lasers has been carried out. The effect of electron leakage on the temperature sensitivity of InGaAsP/InP lasers has been revealed.

Superluminescent diodes (SLDs) employing single and multiple quantum wells were investigated. The diode structure includes a monolithic window and a gain and absorber section. Spectral widths 2–3 times that of conventional SLDs were demonstrated.

Ultralow threshold currents have been obtained in multiquantum well strained-layer InGaAs lasers. A cw threshold current of 1 mA in an uncoated double quantum well laser and a 0.35 mA (pulsed threshold current 0.25 mA) in a coated laser are demonstrated.

al.,' who found that for the specific case of u)/h = 0.101 and t / h = 0.011, the microstrip with a circular-edged strip will have 15% less conductor loss than the microstrip with rectangular edges. For the same configuration, the present technique predicts a 10.7% decrease in loss for a circular cross-section. Conclusion:Microstrip conductor loss can be calculated quickly by a perturbation method which includes the effect of strip edge shape. The work of Lewin and Vainshtein has been extended here to implement the technique on microstrip. The required stopping points in the loss integrations have been found here for a variety of trapezoidal strip edges. Loss calculations have been done for these and other edges, and it is apparent that the edge shape has a significant effect on the conductor loss. Although results here tend to overestimate the effect owing to breakdown of the approximations, conductor loss due to edge shape increases as the edge shape gets sharper and the strip gets narrower or thicker.

An InGaAsP/InP superluminescent diode (SLD) emitting at 1.54 μm has been fabricated. The device uses a buried crescent structure on a p-InP substrate. The parameters were optimized for high output power, small spectral modulation, and smooth far-field operation. The coherence function of the SLD emission was studied systematically. An output power of 5 mW, a coherence length of 41 μm, and a second coherence peak suppression ratio of 22 dB were obtained.