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Presents a study which investigated intense visible emission in the red, green and blue from infrared to visible multiphoton Y[sub1-x]Er[subx]F[sub3] upconversion phosphors pumped with radiation from InGasAsP-laser sources. Sample preparation; Optical spectra; Pump-power dependence.

Presents information on a study which demonstrated that the relaxation oscillation resonance and the resonance in the wavelength chirp can be eliminated by an axially nonuniform photon density. Mechanism that causes the reduction in the resonance due to the result of an antireflective coating; Effect of the microwave power on the optical spectrum; Conclusions.

Describes indium-gallium-arsenic-phosphorus inverted rib waveguide lasers with pulsed current thresholds. Range of the material growth; Light-current characteristics; Light output versus pulsed current dependence at several heat sink temperatures.

Presents a study that examined the growth of gallium arsenide (GaAs)/aluminum-GaAs quantum-well lasers using trimethylamine alane. Methodology; Determination of the epitaxial structure of the quantum well laser; Analysis of the properties of the quantum well laser.

Describes the effect that patterning of the active stripe region has on the emission energy and the thermal stress in gallium arsenide/silicon layers. Effect of thermally deposited silicon dioxide on the overall stress in the active layer; Use of wet chemical etching; Association between the emission energy and the changes in the polarization.

Presents a study which reduced the biaxial tensile stress by post-growth patterning of the gallium arsenide. Experimental details; Stress exhibited by stripe and rectangular patterns; Conclusion.

Investigates the characteristics of gallium arsenide (GaAs)/aluminum GaAs heterostructures which were grown by liquid-phase epitaxy on molecular-beam-coated gallium arsenide on silicon. Details on the crystal growth of the heterostructures; Information on the optical pumping experiments; Luminescence spectra from the gallium arsenid cap layer in room temperature.

Details a study which measured low-frequency noise on small p-i-n indium gallium arsenide/indium phosphide photodiodes designed to be used in optical communication systems. Methods; Results and discussion; Conclusion.

Presents a study which measured the low frequency electrical current noise in double-heterojunction AlGaAs/GaAs laser diodes on gallium arsenide and on silicon substrates. Experimental details; Results and discussion; Conclusion.

Discusses a study on the improved growth conditions by molecular-beam epitaxy and fabrication of state-of-the-art aluminum gallium arsenide (GaAs)/GaAs selectively doped heterostructure transistors and ring oscillators on silicon substrates. Effects of substrate misorientation on 2DEG properties; Properties of the two-dimensional electron gas; Schottky diodes characteristics and doping profiles on undoped gallium arsenide-on-silicon.

Presents a study which examined the growth by molecular beam epitaxy of high-quality Ga[sub0.85]In[sub0.15]As[sub0.13]Sb[sub0.87] active layers with Al[sub0.4]Ga[sub0.6]As[sub0.035]Sb[sub0.96] cladding layers on GaSb substrates by molecular beam epitaxy. Lattice match of the active layer; Observations of optically pumped laser oscillation; Conclusion.

Examines the molecular-beam epitaxy of gallium antimony/aluminum antimony optical device layers on silicon(100). Prblems in the growth of compound semiconductors on silicon; Description of a double heterostructure laser structure; Characteristics of the room-temperature emission.

Presents a study that described the growth conditions to achieve high-quality indium-arsenic-antimony (InAsSb) alloy and abrupt InAsSb/gallium-Sb heterostructure by molecular-beam epitaxy. Reliability of optical pyrometry in determining the growth temperature; Importance of a stable substrate temperature in achieving homogeneous InAsSb composition; Use of double x-ray diffraction measurement and other methods to evaluate the quality of the epilayers.

Low threshold, optically pumped laser oscillation has been obtained using AlGaAs/GaAs double heterostructures grown on Ge-coated Si substrates. The optical pump power for threshold is comparable to similar heterostructures grown on GaAs substrates. Between 20 and 85 °C the threshold temperature dependence is exponential with T0=160 °C. The laser wavelength and the peak of the spontaneous emission of lasers grown on Si substrates are shifted to longer wavelengths relative to bulk GaAs. This results largely from the strain in the plane of the epilayer produced by the difference in the thermal contraction of the layers and the Si substrate on cooling from the growth temperature. [ABSTRACT FROM AUTHOR]

It is found experimentally that the linewidth of a grating loaded external cavity semiconductor laser is inversely proportional to the square of the linear dimension of the overall cavity. This observed behavior is consistent with the existing theories on the linewidth of a laser with an extended passive cavity. A slope of 6.5×105 Hz cm2 is obtained from least-squares fitting the linewidth vs 1/(cavity length)2 curve at 1 mW of power. However, the linewidth reaches a lower limit when the cavity length is extended beyond a certain limit. This result suggests that additional phase noise term should be included in the calculation of linewidths of these extended cavity semiconductor lasers. We also report a value as small as 18 kHz mW in the linewidth vs 1/(power) curve. [ABSTRACT FROM AUTHOR]

Double heterostructures consisting of GaSb active layers with Al0.4Ga0.6Sb cladding layers were grown by molecular beam heteroepitaxy on Si substrates. The intrinsic ∼12% lattice mismatch between the GaSb and the Si at the growth temperature is largely taken up by a GaSb/AlSb superlattice. The larger thermal contraction of the GaSb layer relative to that of Si causes the GaSb layer to be under severe dilatory strain relative to the Si substrate at room temperature. Optically pumped laser emission ranging from 1.62 μm at 80 K to 1.82 μm at 350 K was observed. The threshold varied somewhat nonexponentially with temperature, with a change in slope at ∼250 K. The exponential threshold-temperature dependences at 80 and 300 K are T0=158 and 100 K, respectively, and are higher than previously reported for GaSb lasers. At 300 K the threshold corresponds to an effective current of 12 kA/cm2. [ABSTRACT FROM AUTHOR]

Double heterostructures consisting of InAs0.91 Sb0.09 active layers with Al0.5 Ga0.5Sb cladding layers were grown by molecular beam epitaxy on GaSb substrates. Optically pumped laser emission at 3.9 μm was observed from 80 to 135 K with an exponentially dependent threshold with T0=17 K. At 80 K the threshold corresponds to an effective current of 4 kA/cm2. This value represents a significant reduction when compared with previous results. For a 1-μm-thick active layer the full angular width of the far field at the half intensity point normal to the junction is 40° and is in reasonable agreement with the width calculated from the guide and cladding refractive indices. [ABSTRACT FROM AUTHOR]

Molecular beam epitaxy has been used to grow InAs1-xSbx active layers on GaSb substrates. Lattice matches of better than 10-3 were obtained with x[bar_over_tilde:_approx._equal_to]0.09. Index waveguiding of the relatively low refractive index InAs1-xSbx is obtained by using an adjacent GaSb guiding layer and a lower refractive index Al0.5Ga0.5Sb cladding layer. Optically pumped laser emission at 3.82 μm has been observed from 77 to 135 K with a T0=15.9 K. [ABSTRACT FROM AUTHOR]

A diffraction-coupled laser array has been actively mode locked in an external cavity to yield Gaussian pulses as short a 61-ps full width at half-maximum with a peak power of 1.1 W and an average power of 0.07 W. The array consists of 10 lasers, each 3 μm wide with 9-μm center to center spacing. It emits with a stable double-lobed far-field pattern characteristic of the out-of-phase coupling between neighboring lasers. These arrays may be useful where high peak as well as high average optical powers are required. [ABSTRACT FROM AUTHOR]

Data are presented demonstrating the optically coupled operation of a 3×3 two-dimensional array of AlxGa1-xAs-GaAs vertical-cavity surface-emitting lasers. Room-temperature threshold current for the array is 90 mA, with the device geometry allowing for light emission from the epitaxial side of the device. [ABSTRACT FROM AUTHOR]

Tunable stimualted emission of radiation is achieved in AlxGa1-xAs/GaAs double heterostructures, in which the waveguiding GaAs region consists of a delta-doped doping superlattice. The low-temperature emission energy is 45 meV below the bulk band gap of GaAs for homogeneous optical excitation of the Fabry–Perot cavity. The emission energy is continuously tunable over 35 Å by inhomogeneous excitation of the cavity. [ABSTRACT FROM AUTHOR]