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Title: Harmonic modulation of radiation of an external-feedback semiconductor laser

Abstract

The appearance of the harmonic modulation regime at the Hopf bifurcation point is described analytically for a delayed-feedback semiconductor laser. The second-order delay differential equation with complex coefficients is derived. The frequency of oscillations appearing at the Hopf bifurcation point is determined by the solution of two relatively simple transcendental equations, from which the bifurcation point itself is found. These equations contain dependences on all the control parameters of the problem. The exact upper and lower limits of the oscillation frequency are found. A comparison with numerical results shows that the modulation frequency is preserved almost constant in a broad range of feedback phases. A procedure is proposed for determining the parameters of the laser providing the presence of bifurcations with a passage to oscillations with the specified frequency. The results obtained in the paper are of interest for WDM communication systems. (control of laser radiation parameters)

Authors:
;  [1]
  1. State Research Center of Russian Federation 'Troitsk Institute for Innovation and Fusion Research', Troitsk, Moscow Region (Russian Federation)
Publication Date:
OSTI Identifier:
21466617
Resource Type:
Journal Article
Resource Relation:
Journal Name: Quantum Electronics (Woodbury, N.Y.); Journal Volume: 37; Journal Issue: 2; Other Information: DOI: 10.1070/QE2007v037n02ABEH013213
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; BIFURCATION; COMPARATIVE EVALUATIONS; DIFFERENTIAL EQUATIONS; FEEDBACK; LASER RADIATION; MATHEMATICAL SOLUTIONS; MODULATION; OSCILLATIONS; SEMICONDUCTOR LASERS; ELECTROMAGNETIC RADIATION; EQUATIONS; EVALUATION; LASERS; RADIATIONS; SEMICONDUCTOR DEVICES; SOLID STATE LASERS

Citation Formats

Sukharev, Aleksandr G, and Napartovich, A P. Harmonic modulation of radiation of an external-feedback semiconductor laser. United States: N. p., 2007. Web. doi:10.1070/QE2007V037N02ABEH013213.
Sukharev, Aleksandr G, & Napartovich, A P. Harmonic modulation of radiation of an external-feedback semiconductor laser. United States. doi:10.1070/QE2007V037N02ABEH013213.
Sukharev, Aleksandr G, and Napartovich, A P. Wed . "Harmonic modulation of radiation of an external-feedback semiconductor laser". United States. doi:10.1070/QE2007V037N02ABEH013213.
@article{osti_21466617,
title = {Harmonic modulation of radiation of an external-feedback semiconductor laser},
author = {Sukharev, Aleksandr G and Napartovich, A P},
abstractNote = {The appearance of the harmonic modulation regime at the Hopf bifurcation point is described analytically for a delayed-feedback semiconductor laser. The second-order delay differential equation with complex coefficients is derived. The frequency of oscillations appearing at the Hopf bifurcation point is determined by the solution of two relatively simple transcendental equations, from which the bifurcation point itself is found. These equations contain dependences on all the control parameters of the problem. The exact upper and lower limits of the oscillation frequency are found. A comparison with numerical results shows that the modulation frequency is preserved almost constant in a broad range of feedback phases. A procedure is proposed for determining the parameters of the laser providing the presence of bifurcations with a passage to oscillations with the specified frequency. The results obtained in the paper are of interest for WDM communication systems. (control of laser radiation parameters)},
doi = {10.1070/QE2007V037N02ABEH013213},
journal = {Quantum Electronics (Woodbury, N.Y.)},
number = 2,
volume = 37,
place = {United States},
year = {Wed Feb 28 00:00:00 EST 2007},
month = {Wed Feb 28 00:00:00 EST 2007}
}
  • The effect of external feedback on a single-mode semiconductor laser is estimated by a numerical solution of the nonlinear rate equations, yielding an excellent description experimental results. It is found that the lasing mode with the minimum linewidth is most stable rather than the mode with minimum threshold gain. The transition to the coherence-collapse regime is of particular interest. It usually occurs for feedback fractions approx. = 10/sup -4/, but it may shifted to considerably larger feedback levels by either increasing the emitted optical power, the laser length, or by decreasing the linewidth enhancement factor ..cap alpha...
  • Electrical negative frequency feedback control has been shown to reduce frequency modulation (FM) noise linewidth in semiconductor lasers. The method is based on the direct frequency modulation capability of a semiconductor laser. An error signal is extracted through optical heterodyne frequency discrimination detection using a stable master laser. FM noise is reduced by more than 20 dB and linewidth is reduced by one order of magnitude.
  • We report the first experimental observation of type-II intermittency in an optical system. The type-II intermittency is observed in the light intensity of a GaAs/GaAlAs semiconductor laser with external feedback in the regime of the coherence collapse. We conclude the occurrence of a time-inverted type-II intermittency from the time distribution of the observed intensity breakdowns, with the injection current as control parameter. This interpretation is confirmed by a reconstructed Poincare plot exhibiting the spiraling behavior of the type-II intermittency.
  • We report the stabilization of a laser diode by external phase-conjugate feedback from a broad-area laser diode. The linewidth of the stabilized laser diode was reduced from 5 MHz to 25 kHz, approaching the limit set by the fluctuations of the pump beam for the phase conjugator. Clear evidence of phase conjugation was the observation of paired half-axial side modes spaced at frequencies of {ital c}/4{ital L} with respect to the main mode. {copyright} {ital 1996 Optical Society of America.}
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