Highly coherent long cavity GaAs/AlGaAs single-quantum-well lasers

Journal Article · Fri Sep 01 00:00:00 EDT 1989 · IEEE (Institute of Electrical and Electronics Engineers) Journal of Quantum Electronics; (USA)

DOI:https://doi.org/10.1109/3.35227· OSTI ID:5607900

Larsson, A ^[1]; Andrekson, P A; Jonsson, B; Lindstrom, C ^[2]

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1. Jet Propulsion Lab., California Institute of Technology, Pasadena, CA (US)
2. Dept. of Optoelectronics and Electrical Measurements, Chalmers Univ. of Technology, S-41296 Gothenburg (SE)

The authors report on measurements of the spectral properties of ridge waveguide graded index separate confinement heterostructure single-quantum-well GaAs/AlGaAs lasers. Long cavity lasers (800{mu}m) exhibit remarkably pure single-longitudinal-mode spectra under continuous operation in spite of the short cavity mode spacing. At an output power of 5 mW, the sidemode suppression exceeds 24 dB and the linewidth is 1.5 MHz. This is among the narrowest linewidths reported for solitary AlGaAs lasers. The linewidth-power product is 6.4 MHz mW. Measurements of the linewidth-power product as a function of cavity length L gives an L/sup -2/ dependence in agreement with theory for lasers with small internal loss. No significant deviation from this dependence was observed for lasers short enough to operate at the second quantized state. The results are also used to deduce the linewidth enhancement factor {alpha} at the gain peak wavelength and its dependence on the excitation level. The sublinear gain-carrier density relation in the single quantum well results in an increase in a with increasing carrier density (decreasing cavity length) in contrast to conventional double heterostructure lasers and multiple-quantum-well lasers. In addition, a decrease in {alpha} was observed for lasers operating at the second quantized state due to recovery of the differential gain.

• OSTI ID: 5607900
• Journal Information: IEEE (Institute of Electrical and Electronics Engineers) Journal of Quantum Electronics; (USA), Journal Name: IEEE (Institute of Electrical and Electronics Engineers) Journal of Quantum Electronics; (USA) Vol. 25:9; ISSN 0018-9197; ISSN IEJQA
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
420300* -- Engineering-- Lasers-- (-1989)
ALUMINIUM ARSENIDES
ALUMINIUM COMPOUNDS
AMPLIFICATION
ARSENIC COMPOUNDS
ARSENIDES
CARRIER DENSITY
COHERENT RADIATION
DIMENSIONS
EFFICIENCY
ELECTROMAGNETIC RADIATION
EMISSION
ENERGY-LEVEL TRANSITIONS
GAIN
GALLIUM ARSENIDES
GALLIUM COMPOUNDS
HETEROJUNCTIONS
JUNCTIONS
LASER CAVITIES
LENGTH
PNICTIDES
QUANTUM EFFICIENCY
RADIATIONS
SEMICONDUCTOR JUNCTIONS
STIMULATED EMISSION
WAVEGUIDES