AlGaAs inverted strip buried heterostructure lasers

Inverted strip buried heterostructure lasers have been fabricated. These lasers have threshold currents and quantum efficiencies that are comparable to those of conventional buried heterostructure lasers. The optical mode is confined by a weakly guiding strip loaded waveguide which makes possible operation in the fundamental transverse mode for larger stripe widths than is possible for conventional buried heterostructure lasers. Scattering of the laser light by irregularities in the sidewalls of the waveguide, which can be a serious problem in conventional buried heterostructure lasers, is also greatly reduced in these lasers

Spectral and dynamic characteristics of buried-heterostructure single quantum well (Al,Ga)As lasers

We demonstrate that, as predicted, (Al,Ga)As single quantum well (SQW) lasers have substantially narrower spectral linewidths than bulk double-heterostructure lasers. We have observed a further major reduction (>3×) in the linewidth of these SQW lasers when the facet reflectivities are enhanced. This observation is explained theoretically on the basis of the very low losses in coated SQW lasers and the value of the spontaneous emission factor at low threshold currents. We also report on the modulation frequency response parameter of these SQW lasers

Solar driven lasers for power satellite applications

The technological feasibility of using multimagawatt lasers for space power transmission is discussed. Candidate lasers include electric discharge lasers, direct optically pumped lasers, and free electron lasers

Large optical cavity AlGaAs buried heterostructure window lasers

Large optical cavity buried heterostructure window lasers in which only the transparent AlGaAs waveguiding layers, and not the active layer, extend to the laser mirrors have been fabricated. These lasers have threshold currents and differential quantum efficiencies comparable to those of regular large optical cavity buried heterostructure lasers in which the active region extends to the laser mirrors, however the window lasers have been operated under pulsed conditions at three times the power at which otherwise identical lasers without windows degrade by catastrophic mirror damage

Visible submicron microdisk lasers

The authors describe the performance of submicron microdisk lasers fabricated within InGaP/InGaAlP quantum well material working at room temperature. The smallest lasers, with diameters of approximately 600 nm, feature ultrasmall mode volumes and exhibit single mode operation at low threshold powers. Their small cavity volumes of approximately 0.03 µm^3 enable microdisk lasers to be used as spectroscopic sources. Here the authors demonstrate the fabrication and characterization of visible, monolithically fabricated, submicron microdisk lasers

Very low threshold InGaAsP mesa laser

Very low threshold currents InGaAsP/InP terrace mesa (T-ME) lasers with an unpassivated surface have been fabricated on semi-insulating (SI) InP substrates. Fabrication of the lasers involves a single-step liquid phase epitaxial (LPE) growth and a simple etching process. Lasers operating in the fundamental transverse mode with threshold currents as low as 6.3 mA (for a cavity length of 250 μm) have been obtained. Comparison between the unpassivated lasers and those passivated using the mass transport technique is described

Mode stabilized terrace InGaAsP lasers on semi-insulating InP

Mode stabilized terrace InGaAsP lasers have been fabricated on semi-insulating InP substrates. The fabrication involves a selective, single-step liquid phase epitaxial growth process, and a lateral Zn diffusion. Two versions of the terrace lasers are fabricated, and threshold currents as low as 35 mA and 50 mA respectively are obtained. The lasers operate with a stable single lateral mode. High power performance is observed. These lasers are suitable for monolithic integration with other optoelectronic devices