Filters

2008 - 200912010 - 20182

More filters

20193
Reset filters

Settings

Author: Pimenov, Alexander × Subject: mode-locking ×

Search Results

Now showing 1 - 3 of 3
  • Thumbnail Image
    Item
    Light bullets in a time-delay model of a wide-aperture mode-locked semiconductor laser
    (Berlin : Weierstraß-Institut für Angewandte Analysis und Stochastik, 2018) Pimenov, Alexander; Javaloyes, Julien; Gurevich, Svetlana V.; Vladimirov, Andrei G.
    Recently, a mechanism of formation of light bullets (LBs) in wide-aperture passively modelocked lasers was proposed. The conditions for existence and stability of these bullets, found in the long cavity limit, were studied theoretically under the mean field (MF) approximation using a Haus-type model equation. In this paper we relax the MF approximation and study LB formation in a model of a wide-aperture three section laser with a long diffractive section and short absorber and gain sections. To this end we derive a nonlocal delay-differential equation (NDDE) model and demonstrate by means of numerical simulations that this model supports stable LBs. We observe that the predictions about the regions of existence and stability of the LBs made previously using MF laser models agree well with the results obtained using the NDDE model. Moreover, we demonstrate that the general conclusions based upon the Haus model that regard the robustness of the LBs remain true in the NDDE model valid beyond the MF approximation, when the gain, losses and diffraction per cavity round-trip are not small perturbations anymore.
  • Thumbnail Image
    Item
    Bifurcations in a model of monolithic passively mode-locked semiconductior laser
    (Berlin : Weierstraß-Institut für Angewandte Analysis und Stochastik, 2008) Vladimirov, Andrei; Pimenov, Alexander; Rachinskii, Dmitrii
    Bifurcation mechanisms of the development and break up of different operation regimes in a passively mode-locked monolithic semiconductor laser are studied by solving numerically partial differential equations for amplitudes of two counterpropagating waves and carrier densities in gain and absorber sections. It is shown that harmonic mode-locking regime with two pulses in the cavity can exhibit a period-doubling bifurcation leading to different amplitudes and separations of the pulses. The effect of linewidth enhancement factors in gain and absorber sections on the laser dynamics is discussed.
  • Thumbnail Image
    Item
    Delayed feedback control of self-mobile cavity solitons in a wide-aperture laser with a saturable absorber
    (Berlin : Weierstraß-Institut für Angewandte Analysis und Stochastik, 2017) Schemmelmann, Tobias; Tabbert, Felix; Pimenov, Alexander; Vladimirov, Andrei G.; Gurevich, Svetlana V.
    We investigate the spatiotemporal dynamics of cavity solitons in a broad area vertical-cavity surface-emitting laser with saturable absorption subjected to time-delayed optical feedback. Using a combination of analytical, numerical and path continuation methods we analyze the bifurcation structure of stationary and moving cavity solitons and identify two different types of traveling localized solutions, corresponding to slow and fast motion. We show that the delay impacts both stationary and moving solutions either causing drifting and wiggling dynamics of initially stationary cavity solitons or leading to stabilization of intrinsically moving solutions. Finally, we demonstrate that the fast cavity solitons can be associated with a lateral mode-locking regime in a broad-area laser with a single longitudinal mode.