TREDICCE , Jorge R.

Beyond the chirality of light associated to polarization or spin, light beams can carry an additional orbital angular momentum due to the helicoidal structure of their phase front. This property, if combined with light localization could give rise to localized optical vortices, whose existence in nonlinear and dissipative optical systems is...

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International audience

In this work weexperimentally study mode-hopping in bulk semicnductor lasers. This stochastic process is ruled by Kramers statistics with a decay rate dependeing on the laser parameters of the temperature of the substrate and the puming current....

We report on experimental observation of localized structures in two mutually coupled broad-area semiconductor resonators. These structures coexist with a dark homogeneous background and they have the same properties as cavity solitons without requiring the presence of a driving beam into the system. They can be switched individually on and off...

The response of a Class B laser to a rapid change in one of its parameters is known to be accompanied by delay and ringing. It has been theoretically and numerically shown that the transition can be modified by using adequate functional shapes for the control parameter (e.g., the laser pump) in order to steer the laser from one point of...

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We study the polarization-resolved dynamics of a vertical-cavity surface-emitting laser with mode-matched and polarization-preserving optical feedback. The total power can display low-frequency fluctuations, which are associated with drops in power of the dominant linearly polarized mode and with bursts of power of the depressed mode. However,...

The stable positions of localized structures depend on spatial gradients in the system parameters and on the local defects of the hosting medium. We propose a general method to disclose and visualize the local defects of the medium structure, otherwise not detected. The method is based on the observation of the spatiotemporal behavior of...

ITCOM 2002, Boston MA, 29 juillet-1er août

Cavity solitons (CSs) are localized structures appearing as single intensity peaks in the homogeneous background of the field emitted by a nonlinear (micro) resonator driven by a coherent field (holding beam). By introducing a phase gradient in the holding beam, it is possible to induce CS drift. This motion is strongly influenced by the...

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In this paper, we experimentally analyze the modal dynamics of quantum-well semiconductor lasers. Modal switching is the dominant feature for semiconductor lasers that exhibit two or several active longitudinal modes in their time-averaged optical spectrum. In quantum-well lasers, these dynamics involve a periodic switching among several...

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Critical slowing down near a bifurcation or limit point leads to a dynamical hysteresis that cannot be avoided by sweeping a control parameter slowly through the critical point. This paper analytically illustrates, with the help of a simple model, the bifurcation shift. We describe an inexpensive experiment using a semiconductor laser where...

We analyze theoretically and experimentally how the modal dynamics of quantum-well semiconductor lasers is affected by weak optical feedback. Without feedback, these lasers exhibit a regular switching among several longitudinal modes, following a well determined modal sequence and leaving the total intensity output constant. Using a multimode...

International audience

Cavity solitons are localized intensity peaks that can form in a homogeneous background of radiation. They are generated by shining laser pulses into optical cavities that contain a nonlinear medium driven by a coherent field (holding beam). The ability to switch cavity solitons on and off1, 2 and to control their location and motion3 by...

In this manuscript we analyze the modal dynamics ofmultimode semiconductor quantum-well lasers. Modal switching is the dominant feature of thedevices analyzed and it obeys a highly organized antiphase dynamics which leads to an almost constanttotal intensity output. For each active mode a regular switching at frequencies offew MHz is observed....

Cavity solitons are stationary self-organized bright intensity peaks which form over a homogeneous background in the section of broad area radiation beams. They are generated by shining a writing/erasing laser pulse into a nonlinear optical cavity, driven by a holding beam. The ability to control their location and their motion by introducing...