Search

Your search keyword '"Department of Applied Physics and Photonics [Brussels] ( TONA )"' showing total 121 results
Start Over Author "Department of Applied Physics and Photonics [Brussels] ( TONA )"
121 results on '"Department of Applied Physics and Photonics [Brussels] ( TONA )"'

101. Nonlinear dynamics and polarization bistability in optically injected VCSELs

Author

Krassimir Panajotov, Marc Sciamanna, Hugo Thienpont, Ignace Gatare, Jordi Buesa, Applied Physics and Photonics, Vrije Universiteit Brussel, Laboratoire Matériaux Optiques, Photonique et Systèmes (LMOPS), CentraleSupélec-Université de Lorraine (UL), Department of Applied Physics and Photonics [Brussels] (TONA), and Vrije Universiteit Brussel (VUB)

Subjects
Physics, Period-doubling bifurcation, Bistability, Linear polarization, Orthogonal polarization spectral imaging, business.industry, Nonlinear optics, Semiconductor laser theory, Optical bistability, Injection locking, Optics, [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, Atomic physics, business
Abstract

International audience; We investigate experimentally and theoretically nonlinear dynamics and polarization bistability in a vertical-cavity surface-emitting laser (VCSEL) submitted to an external optical injection with orthogonal polarization, i.e., the injected light from a master laser (ML) is linearly polarized and orthogonal to the polarization direction of the free-running VCSEL (slave laser, SL). Depending on the injection power level and the frequency detuning between ML and SL, our experimental results show that the injected VCSEL may undergo complex dynamics including subharmonic resonances and period-doubling route to chaos that are associated to polarization switching (PS). Using continuation method, we carry out a detailed bifurcation analysis and report on qualitatively different dynamics as we change the injection strength and/or the detuning. We show that PS may be strongly influenced by the presence of those dynamics. Our numerical results reveal period doubling dynamics that emerge from a Hopf bifurcation associated to an elliptical polarized injection locking state. Pure frequency-induced polarization bistability, i.e., when the detuning is changed for fixed injection power, is studied theoretically. Our results show that, depending on the level of the fixed injection strength, frequency induced PS may be achieved with or without hysteresis.

Published
2006
Full Text
View/download PDF

102. Pulse package dynamics in VCSELs with delayed optical feedback from a short external cavity

Author

Sciamanna, M., Tabaka, A., Peil, M., Fischer, Ingo Bert, KRASSIMIR PANAJOTOV, Elsasser, W., Irina Veretennicoff, Hugo Thienpont, Applied Physics and Photonics, Laboratoire Matériaux Optiques, Photonique et Systèmes (LMOPS), CentraleSupélec-Université de Lorraine (UL), Department of Applied Physics and Photonics [Brussels] (TONA), Vrije Universiteit Brussel (VUB), Institute of Applied Physics (IAP), Darmstadt University of Technology [Darmstadt], and Van Luchene, Sébastien

Subjects
[SPI.OPTI] Engineering Sciences [physics]/Optics / Photonic, [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, ComputingMilieux_MISCELLANEOUS, no keywords
Abstract

International audience

Published
2006

103. Polarization switching bistability and dynamics in vertical-cavity surface-emitting laser under orthogonal optical injection

Author

Jordi Buesa, Marc Sciamanna, Ignace Gatare, Hugo Thienpont, Krassimir Panajotov, Applied Physics and Photonics, Laboratoire Matériaux Optiques, Photonique et Systèmes (LMOPS), CentraleSupélec-Université de Lorraine (UL), Department of Applied Physics and Photonics [Brussels] (TONA), and Vrije Universiteit Brussel (VUB)

Subjects
optical injetion, bistability, Bistability, 02 engineering and technology, laser dynamics, 01 natural sciences, law.invention, Vertical-cavity surface-emitting laser, Optical bistability, Semiconductor laser theory, no keywords, polarization switching, 010309 optics, 020210 optoelectronics & photonics, Optics, law, 0103 physical sciences, 0202 electrical engineering, electronic engineering, information engineering, Electrical and Electronic Engineering, Physics, [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], business.industry, Nonlinear optics, Laser, Atomic and Molecular Physics, and Optics, Electronic, Optical and Magnetic Materials, Transverse mode, Injection locking, vertical-cavity surface-emitting lasers (VCSEL), [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, business
Abstract

International audience; Bistability as well as dynamics associated to polarization switching in a vertical-cavity surface-emitting laser (VCSEL) submitted to orthogonal optical injection from an external master laser are investigated. Intensity-polarization switching bistability is studied by increasing and decreasing the intensity of the injected beam and for a fixed frequency detuning, i.e. the frequency offset between master and the free running VCSEL. Depending on the frequency detuning, bistable switching is experimentally found to occur with or without injection locking of the fundamental mode to the master laser frequency. For large positive detuning, injection locking of the first-order transverse mode with a strong depression of the fundamental mode has been observed. The case of frequency – polarization switching bistability, i.e. when the frequency detuning is first decreased and then increased for a fixed injected power, has also been theoretically analyzed. Qualitative comparison with previous experimental work is presented for the dependence of the width of the bistable switching region on the injection strength level. Finally we show an experimental result of complicated dynamics including period doubling route to chaos that accompany polarization switching and which motivates future theoretical investigations.

Published
2006
Full Text
View/download PDF

104. Microlenses fabricated by ultraviolet excimer laser irradiation of poly(methyl methacrylate) followed by styrene diffusion

Author

Lazare, Sylvain, Lopez, John, Turlet, Jean-Marie, Kufner, Maria, Kufner, Stefan, Chavel, Pierre, Laboratoire de Photochemie et Photophysique Moléculaire, Centre National de la Recherche Scientifique (CNRS), Centre de physique moléculaire optique et hertzienne (CPMOH), Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1, Department of Applied Physics and Photonics [Brussels] (TONA), Vrije Universiteit Brussel (VUB), Laboratoire Charles Fabry de l'Institut d'Optique / Scop, Laboratoire Charles Fabry de l'Institut d'Optique (LCFIO), and Centre National de la Recherche Scientifique (CNRS)-Institut d'Optique Graduate School (IOGS)-Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Institut d'Optique Graduate School (IOGS)-Université Paris-Sud - Paris 11 (UP11)

Subjects
[PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics]
Abstract

International audience; A new technique of microlens array fabrication based on the use of excimer laser radiation is described. Poly(methyl methacrylate) (PMMA) substrates are treated with many low-energy KrF laser pulses and exposed to styrene vapor. The irradiated material swells, producing spherical microlenses that are stabilized by UV polymerization. The chemistry of this process and the optical quality of the lenses are discussed.

Published
1996
Full Text
View/download PDF

105. Intrinsic gain switching in optically injected quantum dot laser lasing simultaneously from the ground and excited state

Author

Hugo Thienpont, Lukasz Olejniczak, Sebastian Wieczorek, Marc Sciamanna, Krassimir Panajotov, Laboratoire Matériaux Optiques, Photonique et Systèmes (LMOPS), CentraleSupélec-Université de Lorraine (UL), Department of Applied Physics and Photonics [Brussels] (TONA), Vrije Universiteit Brussel (VUB), Mathematics Research Institute, University of Exeter, and Applied Physics and Photonics

Subjects
Physics, [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], business.industry, Physics::Optics, Statistical and Nonlinear Physics, 02 engineering and technology, Laser pumping, SEMICONDUCTOR-LASERS, 01 natural sciences, Atomic and Molecular Physics, and Optics, Semiconductor laser theory, Gain-switching, Light intensity, 020210 optoelectronics & photonics, Quantum dot laser, Excited state, Picosecond, 0103 physical sciences, 0202 electrical engineering, electronic engineering, information engineering, Optoelectronics, Atomic physics, 010306 general physics, business, Lasing threshold
Abstract

We analyze theoretically nonlinear dynamics of an optically injected two-mode quantum dot laser lasing simultaneously from the ground and excited states. We show that although the external optical signal is injected into the ground-state mode alone, it can lead to the generation of regular picosecond pulses and pulse packages in the intensity of the excited-state mode. Generation of regular streams of picosecond pulses is attributed to an intrinsic gain switching mechanism where the relaxation time is modulated by the oscillations in the occupation of the ground and excited energy states. (C) 2010 Optical Society of America

Published
2010
Full Text
View/download PDF

106. Dynamics of vertical-cavity surface-emitting lasers with optical injection: a two-mode model approach

Author

Ignace Gatare, Hugo Thienpont, Krassimir Panajotov, Michel Nizette, Marc Sciamanna, Optique Nonlinéaire Théorique (ONT), Université libre de Bruxelles (ULB), Laboratoire Matériaux Optiques, Photonique et Systèmes (LMOPS), CentraleSupélec-Université de Lorraine (UL), Department of Applied Physics and Photonics [Brussels] (TONA), Vrije Universiteit Brussel (VUB), and Applied Physics and Photonics

Subjects
SEMICONDUCTOR-LASER, MODULATION BANDWIDTH, 02 engineering and technology, 01 natural sciences, Vertical-cavity surface-emitting laser, law.invention, Semiconductor laser theory, 010309 optics, symbols.namesake, 020210 optoelectronics & photonics, Optics, law, 0103 physical sciences, 0202 electrical engineering, electronic engineering, information engineering, POLARIZATION, FEEDBACK, SUBJECT, DIODES, Bifurcation, Physics, Hopf bifurcation, [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], Oscillation, business.industry, Statistical and Nonlinear Physics, Optical polarization, Polarization (waves), Laser, Atomic and Molecular Physics, and Optics, [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, symbols, Atomic physics, business
Abstract

We present a comprehensive study of the bifurcation routes in a generic model of a two-polarization-mode semiconductor laser when subject to orthogonal optical injection, relevant to a single-transverse-mode verticalcavity surface-emitting laser. For positive detunings, polarization switching (PS) occurs as the intensity of the noninjected mode gradually decreases and eventually shuts down, in some cases accompanied along the way by the onset and the subsequent vanishing of relaxation oscillations. We identify a Hopf bifurcation on a two-polarization-mode solution, which supports the onset of relaxation oscillation time-periodic dynamics in both injected (x-linearly polarized) and noninjected (y-linearly polarized) modes. For sufficiently large negative detunings, PS is a sharp transition occurring either at the injection-locking point or at a subcritical Hopf bifurcation and is often part of a hysteresis cycle. (C) 2009 Optical Society of America

Published
2009
Full Text
View/download PDF

107. Polarization properties and instabilities of QD VCSELs

Author

Lukasz Olejniczak, F. Hopfer, Marc Sciamanna, Alex Mutig, Hugo Thienpont, Krassimir Panajotov, Dieter Bimberg, Laboratoire Matériaux Optiques, Photonique et Systèmes (LMOPS), CentraleSupélec-Université de Lorraine (UL), Department of Applied Physics and Photonics [Brussels] (TONA), Vrije Universiteit Brussel (VUB), Institut für Festkörperphysik, Technische Universität Berlin (TU), and Applied Physics and Photonics

Subjects
Physics, Polarization rotator, Birefringence, Condensed matter physics, business.industry, Linear polarization, SURFACE-EMITTING LASERS, Physics::Optics, 02 engineering and technology, Elliptical polarization, QUANTUM DOTS, EPITAXY, GAIN, 021001 nanoscience & nanotechnology, Polarization (waves), 01 natural sciences, Semiconductor laser theory, Dwell time, 0103 physical sciences, [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, Optoelectronics, 010306 general physics, 0210 nano-technology, business, Quantum well
Abstract

International audience; Quantum well (QW) VCSELs have a tendency to switch their polarization from one linearly polarized (LP) mode to the orthogonal one when changing the operation conditions. As polarization properties of VCSELs are governed by anisotropies, namely stress-induced birefringence and dichroism, the inherent anisotropy of quantum dots (QDs) is expected to influence the polarization properties of QD VCSELs. In this paper we summarize our experimental results on polarization properties of QD VCSELs with the main focus on polarization switching phenomena. Close to threshold the laser emits linearly polarized light which changes to elliptically polarized (EP) at some current. The main axes of these states are not aligned and the angle between them increases with current. As the current is still increased polarization switching accompanied by polarization mode hopping occurs. Distinctive feature of the observed switching is that the two EP states between which switching occurs are nonorthogonal. The angle between their major exes is 40 deg. Polarization mode hopping has been characterized in terms of the dwell time and the current-dependence of this factor examined. Apparently, the dwell time decreases when the pump current is increased which differs from what has been published for QW VCSELs. The average dwell time is 20 ns. Similarly to QW VCSELs the distribution of the dwell time is exponential. The statistics is the same for the two EP states and such symmetric switching is maintained in the whole range of currents at which the light is elliptically polarized. Large-signal modulation experiments show that the frequency at which polarization switching disappears is about 100 MHz. This indicates that the switching is of thermal origin.

Full Text
View/download PDF

108. Vertical integration of an Electro-Absorption Modulator on a VCSEL to reach very high modulation speed

Author

Ludovic Marigo-Lombart, Stéphane Calvez, Alexandre Arnoult, Hugo Thienpont, Krassimir Panajotov, Guilhem Almuneau, Équipe Photonique (LAAS-PHOTO), Laboratoire d'analyse et d'architecture des systèmes (LAAS), Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées, Service Techniques et Équipements Appliqués à la Microélectronique (LAAS-TEAM), Department of Applied Physics and Photonics [Brussels] (TONA), Vrije Universiteit Brussel (VUB), Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université Toulouse Capitole (UT Capitole), and Université de Toulouse (UT)

Subjects
[SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic
Abstract

International audience; The ever-increasing exchange of information translates in a need to develop transmitters presenting increasing modulation capabilities. To-date, the main research strand has aimed to increase the modulation bandwidth of directly-modulated VCSELs essentially through an improvement of their design [1,2]. However, the physical limits due to the carrier dynamics have to be overcome to enable the IEEE 802.3ba standards (100Gbps) to be met. To that extent, coupled-cavity (CC-) VCSEL configurations have been introduced with either lateral coupling [3], or vertically-coupled structures exploiting either electro-optic [4] or electro-absorptive effect to induce the modulation [5]. We worked on the optical design and simulations of Electro-Absorption Modulator vertically integrated with a VCSEL. We have grown different structures, EAMs and EAM-VCSELs, under close in-situ monitoring and with detailed characterization of the resulting epilayers. Preliminary static measurements of the devices subsequently fabricated using a self-aligned process [6] have shown very promising results and on a par with the literature state-of-the-art performance [7]. In Addition, we have also improved our high frequency contact design to decrease the pad capacitance and thereby facilitate wide bandwidth operation.

109. Asymmetric dwell-time statistics of polarization chaos from free-running VCSEL

Author

Marc Sciamanna, Krassimir Panajotov, Elodie Mirisola, Martin Virte, Vrije Universiteit Brussel (VUB), Laboratoire Matériaux Optiques, Photonique et Systèmes (LMOPS), CentraleSupélec-Université de Lorraine (UL), Department of Applied Physics and Photonics [Brussels] (TONA), Applied Physics and Photonics, and Brussels Photonics Team

Subjects
Physics, [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], business.industry, media_common.quotation_subject, Physics::Optics, Polarization (waves), Asymmetry, Atomic and Molecular Physics, and Optics, Vertical-cavity surface-emitting laser, Semiconductor laser theory, SURFACE-EMITTING LASERS, SEMICONDUCTOR-LASERS, DIODE, DYNAMICS, MODE, Dwell time, Optics, Amplitude, Statistics, [NLIN.NLIN-CD]Nonlinear Sciences [physics]/Chaotic Dynamics [nlin.CD], Spontaneous emission, business, Anisotropy, media_common
Abstract

We experimentally report on asymmetric dwell-time statistics of polarization chaos dynamics generated from free-running vertical-cavity surface-emitting lasers (VCSELs). Theoretically, we explain this behavior by introducing a misalignment between the phase and amplitude anisotropy within the spin-flip model for VCSELs. It induces an asymmetry in the VCSEL polarization behavior which is then responsible for significant changes in the statistics of the chaotic mode-hopping with an increase in the average residence time and an inversion of the dominant mode. (C) 2015 Optical Society of America

Full Text
View/download PDF

110. Experimental and theoretical analysis of limit cycle bistability in a free-running VCSEL

Author

Marc Sciamanna, Krassimir Panajotov, Martin Virte, Emeric Mercier, Brussels Photonics Team, Applied Physics and Photonics, Department of Applied Physics and Photonics [Brussels] (TONA), Vrije Universiteit Brussel (VUB), Laboratoire Matériaux Optiques, Photonique et Systèmes (LMOPS), and CentraleSupélec-Université de Lorraine (UL)

Subjects
Physics, Laser diode, Bistability, Physics::Optics, 02 engineering and technology, Elliptical polarization, Polarization (waves), 01 natural sciences, Semiconductor laser theory, law.invention, Vertical-cavity surface-emitting laser, SURFACE-EMITTING LASERS, POLARIZATION PROPERTIES, 020210 optoelectronics & photonics, law, Quantum dot laser, Quantum mechanics, Limit cycle, 0103 physical sciences, [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, 0202 electrical engineering, electronic engineering, information engineering, SEMICONDUCTOR-LASERS, ANISOTROPIES, MODE, 010306 general physics
Abstract

International audience; Laser diodes typically behave like damped oscillators: they are generally expected to only show damped relaxation oscillations toward a stable fixed point. In vertical-cavity surface-emitting lasers (VCSELs), the picture appears to be quite different as polarization dynamics can be experimentally observed including bifurcations to self- pulsation and even chaos. Physically, the circular geometry of VCSELs makes the polarization selection very weak and, thus, the additional degree of freedom can enable complex dynamical behavior in the laser diode. Here we report on a new dynamical behavior in a free-running VCSEL: we observe a bistability between two limit cycles oscillating around two distinct elliptical polarization states whose main axes are symmetrical with respect to the polarization at threshold. Although the existence of two symmetric elliptical polarizations and the associated limit cycles are predicted by the San Miguel, Feng and Moloney (SFM) model, the hysteresis cycle observed experimentally highlights the importance of asymmetry in the dynamics from the elliptically polarized states. We demonstrate that this behavior can be accurately reproduced in theory within the SFM framework when taking into account a small misalignment between the phase and amplitude anisotropies of the laser cavity. Our results bring new light into VCSEL polarization dynamics and provide a very good qualitative agreement with the bifurcation scenario predicted by the SFM model.

Full Text
View/download PDF

111. Design of an Electro-absorption modulator for integration onto a VCSEL

Author

Ludovic Marigo-Lombart, Stephane Calvez, Alexandre Arnoult, Alexandre Rumeau, Christophe Viallon, Hugo Thienpont, Guilhem Almuneau, Krassimir Panajotov, Équipe Photonique (LAAS-PHOTO), Laboratoire d'analyse et d'architecture des systèmes (LAAS), Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT), Service Techniques et Équipements Appliqués à la Microélectronique (LAAS-TEAM), Service Instrumentation Conception Caractérisation (LAAS-I2C), Équipe Microondes et Opto-microondes pour Systèmes de Télécommunications (LAAS-MOST), Department of Applied Physics and Photonics [Brussels] (TONA), Vrije Universiteit Brussel (VUB), SPIE, Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), and Université Fédérale Toulouse Midi-Pyrénées

Subjects
[SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

112. VCSELs fabricated using self-aligned processing

Author

Ludovic Marigo-Lombart, Alexandre Arnoult, Laurent Mazenq, Pascal Dubreuil, Benjamin Reig, Nicolas Mauran, Hugo Thienpont, Krassimir Panajotov, Guilhem Almuneau, Équipe Photonique (LAAS-PHOTO), Laboratoire d'analyse et d'architecture des systèmes (LAAS), Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT), Service Techniques et Équipements Appliqués à la Microélectronique (LAAS-TEAM), Service Instrumentation Conception Caractérisation (LAAS-I2C), Department of Applied Physics and Photonics [Brussels] (TONA), Vrije Universiteit Brussel (VUB), Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), and Université Fédérale Toulouse Midi-Pyrénées

Subjects
stomatognathic diseases, health care facilities, manpower, and services, education, [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, health care economics and organizations, [SPI.MAT]Engineering Sciences [physics]/Materials
Abstract

Oral presentation; International audience

113. Polarization instabilities and nonlinear dynamics in a quantum dot laser

Author

F. Hopfer, Krassimir Panajotov, Alex Mutig, Hugo Thienpont, Dieter Bimberg, Marc Sciamanna, Lukasz Olejniczak, Laboratoire Matériaux Optiques, Photonique et Systèmes (LMOPS), CentraleSupélec-Université de Lorraine (UL), Vrije Universiteit Brussel (VUB), Department of Applied Physics and Photonics [Brussels] (TONA), Institut für Festkörperphysik, Technische Universität Berlin (TU), and Applied Physics and Photonics

Subjects
Physics, [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], Polarization rotator, Condensed matter physics, Linear polarization, business.industry, Nonlinear optics, Physics::Optics, Optical polarization, Elliptical polarization, VCSEL, polarization, optical injection, Polarization (waves), 01 natural sciences, 010305 fluids & plasmas, law.invention, quantum dot (QD), semiconductor laser, Quantum dot laser, law, 0103 physical sciences, Optoelectronics, Quantum well laser, 010306 general physics, business
Abstract

International audience; We demonstrate first experimental evidence of polarization switching in Stranski-Krastanov (SK) and submonolayer (SML) quantum dot (QD) vertical-cavity surface-emitting lasers (VCSELs). In the case of a SMLQD VCSEL polarization switching is accompanied by polarization mode hopping and is associated with a change of linearly polarized light to elliptically polarized one, hence switching takes place between elliptically polarized states. Current-modulation measurements show that the polarization switching is of thermal origin. Exponential decrease of the dwell time with the pump current has been demonstrated as opposed to exponential increase observed in quantum well (QW) VCSELs when polarization mode hopping takes place between orthogonal, linearly polarized states. In the case of SK-QD VCSELs single polarization switching events stimulated by the increase of the wafer temperature have been observed. After the single switching event the polarization of light remains stable at any wafer temperature and pump current while its direction is perpendicular to that before switching. We will furthermore show preliminary theoretical results on the nonlinear dynamics of a QD laser subject to optical injection, paying particular attention to the influence of the linewidth enhancement factor and the intradot transition time-scales.

Full Text
View/download PDF

114. Self-aligned BCB planarization method for high-frequency signal injection in a VCSEL with an integrated modulator

Author

Ludovic Marigo-Lombart, Jean-Baptiste Doucet, Aurélie Lecestre, Benjamin Reig, Bernard Rousset, Hugo Thienpont, Krassimir Panajotov, Guilhem Almuneau, Équipe Photonique (LAAS-PHOTO), Laboratoire d'analyse et d'architecture des systèmes (LAAS), Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées, Service Techniques et Équipements Appliqués à la Microélectronique (LAAS-TEAM), Institut National Polytechnique (Toulouse) (Toulouse INP), Department of Applied Physics and Photonics [Brussels] (TONA), Vrije Universiteit Brussel (VUB), Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université Toulouse Capitole (UT Capitole), and Université de Toulouse (UT)

Subjects
[SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, ComputingMilieux_MISCELLANEOUS, [SPI.MAT]Engineering Sciences [physics]/Materials
Abstract

International audience

115. Random bit generation using polarization chaos from free-running laser diode

Author

Martin Virte, Marc Sciamanna, Krassimir Panajotov, Hugo Thienpont, Emeric Mercier, Brussels Photonics Team, Applied Physics and Photonics, Department of Applied Physics and Photonics [Brussels] (TONA), Vrije Universiteit Brussel (VUB), Laboratoire Matériaux Optiques, Photonique et Systèmes (LMOPS), and CentraleSupélec-Université de Lorraine (UL)

Subjects
SEMICONDUCTOR-LASER, DYNAMICS, FEEDBACK, Chaotic, Laser, 02 engineering and technology, Lyapunov exponent, Optical chaos, 01 natural sciences, law.invention, Semiconductor laser theory, symbols.namesake, 020210 optoelectronics & photonics, Optics, law, 0103 physical sciences, Attractor, 0202 electrical engineering, electronic engineering, information engineering, Electronic engineering, Random Bit Generation, 010306 general physics, Physics, Laser diode, business.industry, Bandwidth (signal processing), Nonlinear Sciences::Chaotic Dynamics, Nonlinear system, Nonlinear Dynamics, [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, symbols, Chaos, business
Abstract

International audience; During the last five years, optical chaos-based random bit generators (RBGs) attracted a lot of attention and demonstrated impressive performances with bit rates up to hundreds of Gbps. However all the suggested schemes use external injection schemes (optical injection or feedback) to turn the lasers into chaos, hence strongly increasing setup complexity. On the other hand, we reported that a laser diode can generate a chaotic output without the need for external perturbation or forcing, hence unveiling a highly simplified way to generate an optical chaos at high frequency. However the low dimension and limited number of positive Lyapunov exponent casted doubts about its direct use for chaos-based applications. Here we make a proof-of-concept demonstration for a Random Bit Generator based on polarization chaos. We therefore suggest a highly simplified RBG scheme using only a free-running laser and small-bandwidth acquisition electronics and demonstrate convincing performances with bit rates up to 100 Gbps without unusual or complex post-processing methods. We link these performances to the double-scroll structure of the chaotic attractor rather than the bandwidth of the dynamics, hence bringing new light on the importance of chaos topology for chaos-based applications. In addition our scheme exhibit a strong potential as it enables a low-cost and/or integrated in parallel on-chip scheme.

Full Text
View/download PDF

116. Experimental study of transverse mode dynamics in vertical-cavity surface-emitting lasers under current modulation

Author

Angel Valle, Marc Sciamanna, Mikel Arizaleta, Krassimir Panajotov, Applied Physics and Photonics, Instituto de Fisica de Cantabria (IFCA), Universidad de Cantabria [Santander]-Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Department of Electric and Electronic Engineering, Universidad Pública de Navarra [Espagne] = Public University of Navarra (UPNA), Department of Applied Physics and Photonics [Brussels] (TONA), Vrije Universiteit Brussel (VUB), Institut of the Solid State Physics (ISSP), Bulgarian Academy of Sciences (BAS), Laboratoire Matériaux Optiques, Photonique et Systèmes (LMOPS), and CentraleSupélec-Université de Lorraine (UL)

Subjects
Physics, current modulation, Multi-mode optical fiber, business.industry, Physics::Optics, Laser, Semiconductor laser theory, law.invention, Transverse mode, Vertical-cavity surface-emitting laser, polarization switching, Transverse plane, Optics, Amplitude, law, Modulation, [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, vertical-cavity surface-emitting laser (VCSEL), nonlinear dynamics, transverse modes, business
Abstract

International audience; In this work we report on an experimental investigation of the nonlinear dynamics of a 850 nm multitransverse mode vertical-cavity surface-emitting laser (VCSEL) when subject to high-frequency current modulation. Different frequencies and modulation amplitudes are applied to the VCSEL. Regular periodic dynamics - with periods equal to the modulation period or twice the modulation period - and irregular pulsating dynamics are obtained. Different dynamical behaviors are illustrated by using power time traces, radio-frequency spectra and bifurcation diagrams. Our results show that irregular pulsating dynamics in multimode VCSELs subject to large-signal current modulatton can be obtained due to the competition between different transverse modes.

Full Text
View/download PDF

117. Experimental evidence of coherence resonance in a time-delayed bistable system

Author

Mikel Arizaleta Arteaga, Miguel Valencia, Marc Sciamanna, Krassimir Panajotov, Hugo Thienpont, Manuel Lopez-Amo, Applied Physics and Photonics, Universidad Pública de Navarra. Departamento de Ingeniería Eléctrica y Electrónica, Nafarroako Unibertsitate Publikoa. Ingeniaritza Elektriko eta Elektronikoa Saila, Department of Applied Physics and Photonics [Brussels] (TONA), Vrije Universiteit Brussel (VUB), Department of Electric and Electronic Engineering, Universidad Pública de Navarra [Espagne] = Public University of Navarra (UPNA), Laboratoire Matériaux Optiques, Photonique et Systèmes (LMOPS), and CentraleSupélec-Université de Lorraine (UL)

Subjects
Coherence time, Bistability, optical noise, General Physics and Astronomy, Physics::Optics, Bistable system with delay, 01 natural sciences, Noise (electronics), 010305 fluids & plasmas, law.invention, Semiconductor laser theory, surface emitting lasers, Coherence resonance, Signal-to-noise ratio, Optics, optical bistability, law, 0103 physical sciences, 010306 general physics, laser cavity resonators, Physics, [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], SURFACE-EMITTING LASERS, STOCHASTIC RESONANCE, NOI, business.industry, delays, Spectral density, Laser, Superluminescent diode, [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, business, optical feedback
Abstract

We report on the experimental observation of coherence resonance in a bistable system with delay. Our system consists of a vertical-cavity surface-emitting laser subject to time-delayed optical feedback simultaneously from a long and from an extremely short external cavity. Coherence resonance is experimentally proven by analysis of the residence time distribution of the polarization mode-hopping regime and of the signal to noise ratio in the power spectrum. The authors acknowledge the financial support of the Public University of Navarra, IAP 6/10 —Belgian Science Policy, FWO Flanders, GOA and OZR of the VUB, Conseil Regional de Lorraine, and Project No. TEC-2004-05936-C02-01 of the MEC (Spain).

Full Text
View/download PDF

118. Polarization switching and polarization mode hopping in quantum dot vertical-cavity surface-emitting lasers

Author

Hugo Thienpont, Marc Sciamanna, Krassimir Panajotov, Lukasz Olejniczak, Dieter Bimberg, Alex Mutig, F. Hopfer, Laboratoire Matériaux Optiques, Photonique et Systèmes (LMOPS), CentraleSupélec-Université de Lorraine (UL), Department of Applied Physics and Photonics [Brussels] (TONA), Vrije Universiteit Brussel (VUB), Institut für Festkörperphysik, Technische Universität Berlin (TU), and Applied Physics and Photonics

Subjects
Materials science, Physics::Optics, 02 engineering and technology, Elliptical polarization, 01 natural sciences, Vertical-cavity surface-emitting laser, 010309 optics, 020210 optoelectronics & photonics, Optics, Quantum Dots, 0103 physical sciences, 0202 electrical engineering, electronic engineering, information engineering, Spontaneous emission, Quantum well, business.industry, Lasers, Equipment Design, Polarization (waves), Atomic and Molecular Physics, and Optics, Equipment Failure Analysis, Refractometry, Dwell time, Quantum dot laser, Quantum dot, Optoelectronics, business, INTENSITY NOISE, KRAMERS
Abstract

We show experimentally that polarization mode hopping in quantum dot vertical cavity surface emitting lasers (VCSELs) takes place between nonorthogonal elliptically polarized modes. In contrast to quantum well VCSELs the average dwell time decreases with injection current. This decrease is by 8 orders of magnitude: from seconds to nanoseconds and is achieved without any modifications of the VCSEL internal anisotropies. The observed scaling happens in a range of currents as wide as 8 times the threshold value. (C) 2011 Optical Society of America

Full Text
View/download PDF

119. Linewidth enhancement factor of semiconductor lasers: Results from round-robin measurements in COST 288

Author

Pascal Landais, Silvano Donati, Ignacio Garces, Frédéric Grillot, T. Fordell, Guido Giuliani, V. Vilokkinen, P. Moreno, Raul Escorihuela, D. Klonidis, M. Chacinski, J. Von Staden, J. Pozo, P. Leinonen, Guillaume Huyet, Andrea Fiore, Marc Sciamanna, Jean-François Hayau, Mika J. Saarinen, Ch. Kouloumentas, M. Pessa, A. Lindberg, Asier Villafranca, Pascal Besnard, Judy M Rorison, Jan Danckaert, Marco Rossetti, Richard Schatz, Ioannis Tomkos, Krassimir Panajotov, Julien Poette, Wolfgang Elsässer, Javier Lasobras, poette, julien, Royal Institute of Technology [Stockholm] (KTH ), Athens Information Technology Center () (AITC), Services répartis, Architectures, MOdélisation, Validation, Administration des Réseaux (SAMOVAR), Institut Mines-Télécom [Paris] (IMT)-Télécom SudParis (TSP), Centre National de la Recherche Scientifique (CNRS), Laboratoire Matériaux Optiques, Photonique et Systèmes (LMOPS), CentraleSupélec-Université de Lorraine (UL), Applied Physics Research Group - Vrije Universiteit Brussel (APHY), Vrije Universiteit Brussel (VUB), Department of Applied Physics and Photonics [Brussels] (TONA), Fonctions Optiques pour les Technologies de l'informatiON (FOTON), Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-École Nationale Supérieure des Sciences Appliquées et de Technologie (ENSSAT)-Télécom Bretagne, Physics, Applied Physics, Applied Physics and Photonics, Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-École Nationale Supérieure des Sciences Appliquées et de Technologie (ENSSAT)-Télécom Bretagne-Centre National de la Recherche Scientifique (CNRS)

Subjects
Materials science, INJECTION-LOCKING, BROADENING FACTOR, ALPHA, [SPI.OPTI] Engineering Sciences [physics]/Optics / Photonic, business.industry, 020208 electrical & electronic engineering, 02 engineering and technology, Semiconductor laser theory, Interferometry, Laser linewidth, Laser interferometry, 020210 optoelectronics & photonics, Optics, Quantum dot laser, 0202 electrical engineering, electronic engineering, information engineering, [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, Optoelectronics, Photonics, business, Frequency modulation
Abstract

Round-Robin measurements on the linewidth enhancement factor are carried out within several laboratories participating to EU COST 289 Action. The a-factor is measured by applying up to 7 different techniques. The obtained results are compared. (C) 2007 Optical Society of America

120. Leader-laggard relationship of chaos synchronization in mutually coupled vertical-cavity surface-emitting lasers with time delay

Author

Krassimir Panajotov, Atsushi Uchida, Takaya Mihara, Marc Sciamanna, Mitsutoshi Ozaki, Hiroyuki Someya, Shigeru Yoshimori, Department of Electronics and Computer Systems, Takushoku University, Department of Information and Computer Sciences, Saitama University, Department of Applied Physics and Photonics [Brussels] (TONA), Vrije Universiteit Brussel (VUB), Laboratoire Matériaux Optiques, Photonique et Systèmes (LMOPS), CentraleSupélec-Université de Lorraine (UL), and Applied Physics and Photonics

Subjects
optical chaos, synchronisation, Chaotic, Optical communication, Physics::Optics, 02 engineering and technology, Optical chaos, 01 natural sciences, Synchronization, law.invention, Semiconductor laser theory, 010309 optics, surface emitting lasers, 020210 optoelectronics & photonics, Optics, law, 0103 physical sciences, 0202 electrical engineering, electronic engineering, information engineering, optical communication, Physics, [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], business.industry, Synchronization of chaos, Laser, OPTICAL-INJECTION, DYNAMICS, SUBJECT, SEMICONDUCTOR-LASERS, Wavelength, business
Abstract

International audience; We experimentally and numerically observe synchronization of chaos in two mutually coupled vertical-cavity surface-emitting lasers (VCSELs) with time delay. We observe in-phase and antiphase synchronization of polarization-resolved chaotic temporal wave forms under the condition of wavelength matching. We investigate leader-laggard relationship between two chaotic wave forms of mutually coupled VCSELs and find that the laser with longer wavelength becomes the leader.

Full Text
View/download PDF

121. VCSELs fabricated using self-aligned processing

Author

Ludovic Marigo-Lombart, Laurent Mazenq, Ludovic Salvagnac, Guillaume Libaude, Bernard Rousset, Benjamin Reig, Pascal Dubreuil, Nicolas Mauran, Alexandre Arnoult, Hugo Thienpont, Krassimir Panajotov, Guilhem Almuneau, Équipe Photonique (LAAS-PHOTO), Laboratoire d'analyse et d'architecture des systèmes (LAAS), Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT), Service Techniques et Équipements Appliqués à la Microélectronique (LAAS-TEAM), Service Instrumentation Conception Caractérisation (LAAS-I2C), Department of Applied Physics and Photonics [Brussels] (TONA), Vrije Universiteit Brussel (VUB), Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), and Université Fédérale Toulouse Midi-Pyrénées

Subjects
[SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, ComputingMilieux_MISCELLANEOUS, [SPI.MAT]Engineering Sciences [physics]/Materials
Abstract

International audience

Catalog

Books, media, physical & digital resources
See catalog results