[en] The power and spectral characteristics of pulsed laser diode arrays operating in the spectral range of 850–870 nm and based on heterostructures of two different types (with narrow and wide waveguides) are studied. It is found that the power—current characteristics of the laser arrays of both types are linear within the pump current range of 10–50 A and that the steepness of these characteristics decreases at currents exceeding 80 A. The decrease in the slope efficiency is more noticeable for laser arrays based on heterostructures with wide waveguides. (semiconductor lasers. physics and technology)

[en] Two series of AlGaAs/GaAs laser heterostructures have been grown by metal-organic vapour phase epitaxy, and 808-nm laser diode bars fabricated from the heterostructures have been investigated. The heterostructures differed in waveguide thickness and quantum well depth. It is shown that increasing the barrier height for charge carriers in the active region has an advantageous effect on the output parameters of the laser sources in the case of the heterostructures with a narrow symmetric waveguide: the slope of their power – current characteristics increased from 0.9 to 1.05 W A^-1. Thus, the configuration with a narrow waveguide and deep quantum well is better suited for high-power laser diode bars under hindered heat removal conditions. (lasers)

[en] 

Abstract—

This paper presents results of a comparative experimental study aimed at producing GaAs/GaInP and GaAs/AlGaAs quantum wells (QWs) by metalorganic vapor phase epitaxy. The photoluminescence signal of the GaAs/GaInP QWs is shown to have a higher intensity (by a factor of 50–100) and, at the same time, a larger width (by a factor of ~2.5) in comparison with the GaAs/AlGaAs QWs. We analyze different approaches to controlling emission spectra of these QWs.

[en] A pulsed quantum cascade laser emitting in the wavelength range 9.5–9.7 μm at 77.4 K is developed based on the GaAs/Al_0.45Ga_0.55As heteropair. The laser heterostructure was grown by MOCVD. The threshold current density was 1.8 kA cm^-2. The maximum output power of the laser with dimensions of 30 μm × 3 mm and with cleaved mirrors exceeded 200 mW. (lasers)

[en] Surface segregation during epitaxial growth of stressed InGaAs/GaAs quantum-well heterostructures significantly distorts the nominal concentration profile of quantum wells. The consideration of the effect for growth conditions and elastic stresses appearing during epitaxy on segregation made it possible to simulate the concentration profile with a high accuracy and to calculate the electroluminescence wavelength of actual InGaAs/GaAs heterostructures with quantum wells. It was shown that the observed effect of the long-wave-length shift for the interband transition wavelength in the important case of heterostructures with two neighboring quantum wells is caused by the influence of elastic stresses during growth.