Cavity solitons in vertical-cavity surface-emitting lasers

We investigate a control of the motion of localized structures of light by means of delay feedback in the transverse section of a broad area nonlinear optical system. The delayed feedback is found to induce a spontaneous motion of a solitary localized structure that is stationary and stable in the absence of feedback. We focus our analysis on an experimentally relevant system namely the Vertical-Cavity Surface-Emitting Laser (VCSEL). In the absence of the delay feedback we present experimental evidence of stationary localized structures in a 80 $\mu$m aperture VCSEL. The spontaneous formation of localized structures takes place above the lasing threshold and under optical injection. Then, we consider the effect of the time-delayed optical feedback and investigate analytically the role of the phase of the feedback and the carrier lifetime on the self-mobility properties of the localized structures. We show that these two parameters affect strongly the space time dynamics of two-dimensional localized structures. We derive an analytical formula for the threshold associated with drift instability of localized structures and a normal form equation describing the slow time evolution of the speed of the moving structure.Comment: 7 pages, 5 figure

Polarization properties of localized structures in VCSELs

Broad area Vertical-Cavity Surface-Emitting Lasers (VCSELs) have peculiar polarization properties which are a field of study by itself. These properties have already been used for localized structure generation, in a simple configuration, where only one polarization component was used. Here, we present new experimental and theoretical results on the complex polarization behavior of localized structures generated in an optically-injected broad area VCSEL. A linear stability analysis of the spin-ip VCSEL model is performed for the case of broad area devices, in a restrained and experimentally relevant parameter set. Numerical simulations are performed, in one and two dimensions. They reveal existence of vector localized structures. These structures have a complex polarization state, which is not simply a linear polarization following the one of the optical injection. Experimental results confrm theoretical predictions. Applications of this work can lead to the encoding of small color images in the polarization state of an ensemble of localized structures at the surface of a broad area VCSEL

Vectorial dark dissipative solitons in Kerr resonators

We report the existence of vectorial dark dissipative solitons in optical cavities subject to a coherently injected beam. We assume that the resonator is operating in a normal dispersion regime far from any modulational instability. We show that the vectorial front locking mechanism allows for the stabilisation of dark dissipative structures. These structures differ by their temporal duration and their state of polarization. We characterize them by constructing their heteroclinic snaking bifurcation diagram showing evidence of multistability within a finite range of the control parameter.Comment: \copyright 2021 Optical Society of America. Users may use, reuse, and build upon the article, or use the article for text or data mining, so long as such uses are for non-commercial purposes and appropriate attribution is maintained. All other rights are reserve

Delay feedback induces a spontaneous motion of two-dimensional cavity solitons in driven semiconductor microcavities

We consider a broad area vertical-cavity surface-emitting laser (VCSEL) operating below the lasing threshold and subject to optical injection and time-delayed feedback. We derive a generalized delayed Swift-Hohenberg equation for the VCSEL system, which is valid close to the nascent optical bistability. We first characterize the stationary-cavity solitons by constructing their snaking bifurcation diagram and by showing clustering behavior within the pinning region of parameters. Then, we show that the delayed feedback induces a spontaneous motion of two-dimensional (2D) cavity solitons in an arbitrary direction in the transverse plane. We characterize moving cavity solitons by estimating their threshold and calculating their velocity. Numerical 2D solutions of the governing semiconductor laser equations are in close agreement with those obtained from the delayed generalized Swift-Hohenberg equation

Vector cavity solitons in broad area Vertical-Cavity Surface-Emitting lasers

We report the experimental observation of two-dimensional vector cavity solitons in a Vertical-Cavity Surface-Emitting Laser (VCSEL) under linearly polarized optical injection when varying optical injection linear polarization direction. The polarization of the cavity soliton is not the one of the optical injection as it acquires a distinct ellipticity. These experimental results are qualitatively reproduced by the spin-flip VCSEL model. Our findings open the road to polarization multiplexing when using cavity solitons in broad-area lasers as pixels in information technology

Experimental observation of localized structures in medium size VCSELs

We report experimental evidence of spontaneous formation of localized structures in a 80μm diameter Vertical-Cavity Surface-Emitting Laser (VCSEL) biased above the lasing threshold and under optical injection. Such localized structures are bistable with the injected beam power and the VCSEL current. We experimentally investigate the formation of localized structures for different detunings between the injected beam and the VCSEL, and different injection beam waists