2010, Vladimirov, Andrei, Bandelow, Uwe, Fiol, Gerrit, Arsenijevi´c, Dejan, Kleinert, Moritz, Bimberg, Dieter, Pimenov, Alexander, Rachinskii, Dmitrii

Operation regimes of a two section monolithic quantum dot (QD) mode-locked laser are studied experimentally and theoretically, using a model that takes into account carrier exchange between QD ground state and 2D reservoir of a QD-in-a-well structure, and experimentally. It is shown analytically and numerically that, when the absorber section is long enough, the laser exhibits bistability between laser off state and different mode-locking regimes. The Q-switching instability leading to slow modulation of the mode-locked pulse peak intensity is completely eliminated in this case. When, on the contrary, the absorber length is rather short, in addition to usual Q-switched mode-locking, pure Q-switching regimes are predicted theoretically and observed experimentally.

2006, Viktorov, Evgeny, Mandel, Paul, Vladimirov, Andrei, Bandelow, Uwe

We propose a model for passive mode-locking in quantum dot laser and report on specific dynamical properties of the regime which is characterized by a fast gain recovery. No Q-switching instability has been found accompanying the mode-locking. Bistability can occur between the mode-locking regime and zero intensity steady state.

2010, Vladimirov, Andrei, Lefever, René, Tlidi, Mustapha

The performance of a multisection DBR semiconductor laser emitting around 1060 nm is experimentally and theoretically investigated. Simulations and mode analysis of the traveling wave model including temperature induced changes of the refractive index explain experimentally observed nearly-periodic transitions between neighboring cavity mode determined continuous wave states with increasing injection current.

2006, Turaev, Dmitry, Vladimirov, Andrei, Zelik, Sergey

A new type of stable dynamic bound state of dissipative localized structures is found. It is characterized by chaotic oscillations of distance between the localized structures, their phase difference, and the center of mass velocity.

2009, Jechow, Andreas, Lichtner, Mark, Menzel, Ralf, Radziunas, Mindaugas, Skoczowsky, Danilo, Vladimirov, Andrei

Stripe-array diode lasers naturally operate in an anti-phase supermode. This produces a sharp double lobe far field at angles α depending on the period of the array. In this paper a 40 emitter gain guided stripe-array laterally coupled by off-axis filtered feedback is investigated experimentally and numerically. We predict theoretically and confirm experimentally that at doubled feedback angle 2α a stable higher order supermode exists with twice the number of emitters per array period. The theoretical model is based on time domain traveling wave equations for optical fields coupled to the carrier density equation taking into account diffusion of carriers. Feedback from the external reflector is modeled using Fresnel integration.

2010, Babushkin, Ihar, Bandelow, Uwe, Vladimirov, Andrei

We investigate theoretically the dynamics of three low-order transverse modes in a small-area vertical cavity surface emitting laser. We demonstrate the breaking of axial symmetry of the transverse field distribution in such a device. In particular, we show that if the linewidth enhancement factor is sufficiently large dynamical regimes with broken axial symmetry can exist up to very high diffusion coefficients 10 um^2/ns.

2008, Amiranashvili, Shalva, Vladimirov, Andrei, Bandelow, Uwe

The nonlinear Schrödinger equation based on the Taylor approximation of the material dispersion can become invalid for ultrashort and few-cycle optical pulses. Instead, we use a rational fit to the dispersion function such that the resonances are naturally accounted for. This approach allows us to derive a simple non-envelope model for short pulses propagating in one spatial dimension. This model is further investigated numerically and analytically.

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.

2007, Tlidi, Mustapha, Mussot, Arnaud, Louvergneaux, Eric, Kozyreff, Gregory, Vladimirov, Andrei, Taki, Abdelmajid

Taking up to fourth order dispersion effects into account, we show that fiber resonators become stable for large intensity regime. The range of pump intensities leading to modulational instability becomes finite and controllable. Moreover, by computing analytically the thresholds and frequencies of these instabilities, we demonstrate the existence of a new unstable frequency at the primary threshold. This frequency exists for arbitrary small but nonzero fourth order dispersion coefficient. Numerical simulations for a low and flattened dispersion photonic crystal fiber resonator confirm analytical predictions and opens the way to experimental implementation.