Remarkable reduction of threshold current density of 670 nm GaInAsP/AlGaAs visible lasers by increasing al content of AlGaAs cladding layers

In this report, we present data on an InGaAs/GaAs strained single quantum well laser with the lowest reported threshold current density to date, namely 44 A cm−2 for a 3 mm cavity length. This was grown by solid-source molecular-beam epitaxy with the arsenic dimer, As2. The structure is that of a graded-index, separate-confinement heterostructure with a single strained InGaAs quantum well, sandwiched between GaAs barrier layers and AlGaAs cladding layers. The wavelength of the lasers was around 985 nm, and the internal efficiency and losses were 69% and 0.70 cm−1, respectively. In addition, data on the uniformity of our lasers, which are grown on rotating 2 in substrates (1 in = 2.54 cm), show drops in photoluminescence emission wavelength and layer thickness of less than 4 nm and 4%, respectively, from the centre to the edge of the wafer and very little compositional change.

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Remarkable reduction of threshold current density by substrate misorientation effects in 660 nm visible light lasers with GaInP bulk active layers

Applied Physics Letters ◽

10.1063/1.106439 ◽

1992 ◽

Vol 60 (9) ◽

pp. 1046-1048 ◽

Cited By ~ 15

Author(s):

Akihiko Kikuchi ◽

Katsumi Kishino

Keyword(s):

Visible Light ◽

Current Density ◽

Threshold Current ◽

Threshold Current Density ◽

Active Layers ◽

Remarkable Reduction

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Рабочие характеристики полупроводниковых лазеров на квантовых ямах в зависимости от ширины волноводной области

Физика и техника полупроводников ◽

10.21883/ftp.2021.12.51711.9721 ◽

2021 ◽

Vol 55 (12) ◽

pp. 1229

Author(s):

З.Н. Соколова ◽

Н.А. Пихтин ◽

С.О. Слипченко ◽

Л.В. Асрян

Keyword(s):

Output Power ◽

Current Density ◽

Optical Loss ◽

Optical Power ◽

Pump Current ◽

Threshold Current ◽

Threshold Current Density ◽

Operating Characteristics ◽

Optical Confinement ◽

Cladding Layers

Operating characteristics of semiconductor quantum well (QW) lasers are theoretically studied in terms of the thickness of the waveguide region [optical confinement layer (OCL)]. We calculate the maximum modal gain, optical confinement factor (in QW, OCL, and cladding layers), threshold current density, electron and hole densities (in QW and OCL), internal optical loss (in QW, OCL, and cladding layers), internal differential quantum efficiency, stimulated and spontaneous recombination currents, and output optical power of the laser as functions of the OCL thickness. It is shown that up to the pump current density 50 kA/cm2 the output power of the considered lasers depends only slightly on the OCL thickness in the range of thicknesses 1.5–2.8 m. This result is important for designing high brightness lasers as broadened waveguides are used in such lasers to attain low beam divergence. At high pump current densities, the output power is shown to have a maximum as a function of the OCL thickness.

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