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Doré, François. "Emetteurs à îlots quantiques pour le moyen-infrarouge". Rennes, INSA, 2008. http://www.theses.fr/2008ISAR0024.
Pełny tekst źródłaType I band lineups calculation for narrow gap structures on InP(001) substrate are presented It reveals the interest of InAsSb/GaAsSb association. Single dot model show a mixing of valence and conduction eigenfunctions in the confined eigenstates. This effect leads to non-radiative relaxations. Geometry has a strong impact on related characteristic times. IVBA calculations show a negative trend towards long wavelengths except for favoured areas. Large gap of strained InAs implies the use of big islands with low densities. Gain is then reduced. A 4 QD layers laser emitting at 1. 85 µm at 20 K has a threshold current density of 3,4 kA/cm². InAsSb dots formation in GaAsSb barrier turns out to be difficult. Antimony presence on the surface inhibits 2D-3D transition. Nevertheless this effect permits the formation of larger dots or thicker wells emitting until 2. 35 µm at 300 K
Ding, Shihao. "Exploring nonlinear dynamics and amplitude squeezing of quantum dot lasers". Electronic Thesis or Diss., Institut polytechnique de Paris, 2024. http://www.theses.fr/2024IPPAT008.
Pełny tekst źródłaPhotonic integrated circuits (PICs) utilizing silicon photonics technology show significant potential in high-speed communication systems, optical computing, and quantum technology. Quantum dot (QD) lasers, particularly those epitaxially grown on silicon, exhibit notable characteristics such as strong defect tolerance, low threshold current, and good temperature stability. As a result, they are gradually emerging as promising on-chip laser sources for PICs. This thesis aims to explore the nonlinear dynamics and quantum state properties of QD lasers, laying the foundation for various potential applications. The first section of the thesis delves into the role of the linewidth enhancement factor (αH-factor) in QD lasers. I employed an optical phase modulation technique to extract the above-threshold αH-factor of QD lasers. The small αH-factor of QD lasers strongly improved optical feedback tolerance. This facilitates the development of high-speed optical transmission on chips without an optical isolator and increases integration density. The second section explores the dynamic characteristics of QD lasers under optoelectronic feedback (OEF). Unlike optical feedback, I demonstrated that QD lasers exhibit enhanced sensitivity to OEF, leading to various complex dynamics. This extreme sensitivity is crucial for the advancement of on-chip silicon-based optical computing and Ising machine applications, a phenomenon not observed in quantum well (QW) lasers. In the third section, I analyzed the dependency of frequency noise on external carrier noise. The research revealed that quiet pumping is highly advantageous for minimizing the αH-factor, reducing frequency noise, and consequently narrowing the optical linewidth of QD lasers. The last section highlights the generation of amplitude-squeezed light directly from a constant-current-driven semiconductor QD laser. With the quiet pump, I achieved a substantial gigahertz squeezing bandwidth at room temperature with a squeezing ratio of 3.5 dB. The extreme reflection insensitivity of the squeezed QD generator under optical feedback, in contrast to a reference laser using standard QW technology, is also demonstrated with a squeezing ratio further improved to 5.7 dB. Three distinct measurements, including the sub-shot-noise radiofrequency spectrum, sub-Poissonian photon statistics, and second-order correlation function at zero delay, validate my findings. This research establishes a foundational framework for compact and highly efficient photonic quantum integrated circuits, showcasing the immense application potential of QD lasers in both classical and quantum photonics fields
Hayau, Jean-François. "Caractérisation de composants photoniques à base d'ïlots quantiques à semi-conducteurs InAs/InP : bruit et injection optique". Rennes 1, 2009. https://tel.archives-ouvertes.fr/tel-00511839.
Pełny tekst źródłaHao, Zhenyu. "Caractérisations de structures à base d'îlots, bâtonnets quantiques en termes de bruit, non linéarité et d'injection optique". Phd thesis, Université Rennes 1, 2013. http://tel.archives-ouvertes.fr/tel-00940272.
Pełny tekst źródłaDong, Bozhang. "Quantum-dot lasers on silicon : nonlinear properties, dynamics, and applications". Electronic Thesis or Diss., Institut polytechnique de Paris, 2021. http://www.theses.fr/2021IPPAT047.
Pełny tekst źródłaSilicon photonics is promising for high-speed communication systems, short-reach optical interconnects, and quantum technologies. Direct epitaxial growth of III-V materials on silicon is also an ideal solution for the next generation of photonic integrated circuits (PICs). In this context, quantum-dots (QD) lasers with atom-like density of states are promising to serve as the on-chip laser sources, owing to their high thermal stability and strong tolerance for the defects that arise during the epitaxial growth. The purpose of this dissertation is to investigate the nonlinear properties and dynamics of QD lasers on Si for PIC applications. The first part of this thesis investigates the dynamics of epitaxial QD lasers on Si subject to external optical feedback (EOF). In the short-cavity regime, the QD laser exhibits strong robustness against parasitic reflections hence giving further insights for developing isolator-free PICs. In particular, a near-zero linewidth enhancement factor is crucial to achieve this goal. The second part is devoted to studying the static properties and dynamics of a single-frequency QD distributed feedback (DFB) laser for uncooled and isolator-free applications. The design of a temperature-controlled mismatch between the optical gain peak and the DFB wavelength contributes to improving the laser performance with the increase of temperature. The third part of this dissertation investigates the QD-based optical frequency comb (OFC). External control techniques including EOF and optical injection are used to optimize the noise properties, reduce the timing-jitter, and increase the frequency comb bandwidth. In the last part, an investigation of the optical nonlinearities of the QD laser on Si is carried out by the four-wave mixing (FWM) effect. This study demonstrates that the FWM efficiency of QD laser is more than one order of magnitude higher than that of a commercial quantum-well laser, which gives insights for developing self-mode-locked OFCs based on QD. All these results allow for a better understanding of the nonlinear dynamics of QD lasers and pave the way for developing high-performance classical and quantum PICs on Si
CAVELIER, MARC. "Etude de la dynamique des lasers a semiconducteurs : lasers a puits quantiques et lasers conventionnels". Paris 11, 1992. http://www.theses.fr/1992PA112237.
Pełny tekst źródłaLamkadmi, Azouigui Shéhérazade. "Lasers à boîtes quantiques et tolérance à la rétroaction optique". Evry, Institut national des télécommunications, 2008. http://www.theses.fr/2008TELE0007.
Pełny tekst źródłaHayau, Jean-Francois. "Caractérisation de composants photoniques à base d'îlots quantiques à semi-conducteurs InAs/InP : bruit et injection optique". Phd thesis, Université Rennes 1, 2009. http://tel.archives-ouvertes.fr/tel-00511839.
Pełny tekst źródłaYao, Jun. "Étude des non-linéarités optiques et des effets de capture des porteurs dans les lasers semi-conducteurs à puits quantiques /". Paris : École nationale supérieure des télécommunications, 1994. http://catalogue.bnf.fr/ark:/12148/cb35691387x.
Pełny tekst źródłaOlejniczak, Lukasz. "Polarization properties and nonlinear dynamics of quantum dot lasers". Thesis, Metz, 2011. http://www.theses.fr/2011METZ001S/document.
Pełny tekst źródłaIn this thesis we first show our experimental results on polarization instabilities in quantum dot (QD) lasers with vertical cavity, so called VCSELs. Their characteristics are different from what is typically observed in their QW counterparts: light that is linearly polarized close to lasing threshold becomes elliptically polarized as current is increased and then a wide region of polarization mode hopping between nonorthogonal, elliptically polarized modes sets on. Within this region the average dwell time decreases by eight orders of magnitude from seconds to nanoseconds. To our best knowledge this is the first observation of such a diversified dynamics of polarization mode hopping in a single VCSEL. We have also carried out theoretical studies of optically injected QD lasers accounting for the intradot carrier dynamics through the higher-energy excited states. We show that experimentally observed excitable pulses are complemented by self-pulsations resulting from the so-called bottleneck phenomenon. Finally, we have theoretically investigated optically injected QD laser lasing simultaneously from the ground and excited states. We show that although the external light is injected to the ground state mode alone, modulation of the relaxation time induced by injected signal can provide a gain switching mechanism leading to generation of picosecond pulses from the excited state
Olivier, Augustin. "Contribution à l'étude des propriétés dynamiques des lasers semiconducteurs 1,5 um à multipuits quantiques". Lille 1, 1990. http://www.theses.fr/1990LIL10075.
Pełny tekst źródłaBerger, Pierre-Damien. "Application de la technique de photo réflectivité à la caractérisation de microcavités semi-conductrices". Lyon, INSA, 1997. http://www.theses.fr/1997ISAL0093.
Pełny tekst źródłaThe purpose of this work was to perform an optical characterization of microcavity structures grown by molecular beam epitaxy in III-V semiconductor alloys. We use the photo-reflectance modulation spectroscopy, a non-destructive method, to characterize these structures. Photo-reflectance allows to accurately measure the Fabry-Pérot cavity mode and the quantum well fundamental transition energy, even in the high reflectivity range. Moreover, photo-reflectance spectrum gives the composition of the cavity ternary alloy, the built-in electric field value, and the quantum well thickness. These results are used to calibrate the growth parameters. As part of the project with the CENLETI, we have completed a modelling of the structure reflectivity concerning the active layer influence. We have modelled the excitonic contribution absorption using a Lorentzian model. Experimental PR results are in good agreement with the reflectivity simulation of the structure taking account of the quantum confined Stark effect and electric field effect. If transitions are shifted one regard to the other, an anticrossing behavior appears when the excitonic state is resonant with the Fabry-Pérot cavity mode. Both states are coupled and separated by the Rabi splitting. These mixed states, also called cavity polaritons, can be considered as the result of a periodic oscillation of the energy between the exciton and the photon part of the state. We have performed PR measurements on a VCSEL structure (GaAs/AlGaAs) showing a weak coupling regime with a Rabi splitting of 3. 2meV. The results of simulation are in good agreement with these experimental values. We have also observed a strong coupling regime in a microcavity structure (lnGaAs/AJGaAs/GaAs) with a splitting of 8. 2meV
Benveniste, Elsa. "Etude du gain des lasers à cascade quantique dans le moyen infrarouge". Paris 7, 2009. http://www.theses.fr/2009PA077215.
Pełny tekst źródłaQuantum cascade lasers (QCL) have experienced a constant development since their invention in 1994 and represent so far the most interesting compact source for optical Systems operating in the mid-infrared and in the THz region of the spectrum. In order to respond to applications4s requirements, it is important to study the key physical parameters of the gain in QCL. In the first part of this work, we studied the impact on the gain of the material properties, such as the electron effective mass. In the second part of this work, we realized a new experimental technique for an accurate measurement of the gain, as a function of the voltage applied to the device. Thanks to this technique, we studied several parameters, which have an influence on the laser's performances, such as losses, transparency current, electronic and lattice temperature. Our experimental results were also used to estimate the population inversion on the laser transition and showed the possibility of probing the population of the QCL's electronic states as a function of the bias and the time
Platz, Charly. "Lasers à boîtes quantiques InAs/InP émettant à 1. 55 micromètre pour les télécommunications optiques". Rennes, INSA, 2004. http://www.theses.fr/2004ISARA001.
Pełny tekst źródłaThis thesis investigates InAs/InP quantum dot laser emitting at 1. 55 micron for optical telecommunication applications. The nanometric scaled dimensions of the dots give quantum dots remarkable properties in between bulk semiconductor and atomic electronic structure configuration. First, a dot "seed-growth" model, allowing to predict the influence of growth parameters on dot formation is presented. Growth parameters are investigated to optimise quantum dot properties. The dot electronic structure is calculated in real space or momentum space. The second takes into account the in-plane coupling effect role of the wetting layer between dots. Theoretical optical absorption spectrum using first calculation method is presented. Laser emission is demonstrated at room temperature under optical injection and under electrical injection. . The end of the chapter proposes methods for analysing the complex filling of localized quantum dot levels
Nakkar, Abdul Hadi. "Etude des propriétés optiques de boites quantiques InAs/InP (113)B pour des applications lasers". Rennes, INSA, 2009. http://www.theses.fr/2009ISAR0019.
Pełny tekst źródłaIII-V semiconductor quantum dots (QDs) have attracted much attention during the last twenty years, from fundamental aspects to applications in optoelectronics. InAs/InP(113B) system allows to realise lasers operating in the 1. 55µm window. After a general introduction on physical properties of quantum dots and their method of elaboration by molecular beam epitaxy (MBE) and characterisation by CW photoluminescence (PL), we first emphasis on the study of the correlation of PL and structural atomic force microscopy (AFM) observations on surface QDs (SQDs) grown under various conditions and different GaInAsP buffer layers. The influence of elaboration conditions on capped QD dispersion and morphology is then analysed. A method for improving the QD homogeneity is proposed. A low PL emission linewidth and high PL intensity is reached. Different solutions are then presented to reach emission wavelength above 1,6µm. High arsenic pressure QD growth conditions leads to the formation QDs emitting up to 2µm for a single QD layer. The stacking of 6 QD layers permits to achieve longer wavelength emission (2,46µm) at room temperature. He PL polarisation emission properties of QDs is then analysed, within the QD plane and in TE/TM modes. The in plane polarisation ratio is studied for different QD morphologies. The effect of stacking on the QD morphology, organisation and density shows a clear correlation with polarisation PL observations. The vertical coupling of QDs leads to a quasi equality of TE and TM polarisation modes, which is promising for optical amplification applications
Caroff-Gaonac'h, Philippe. "Croissance de boites quantiques InAs/Inp (113) B pour les applications en télécommunications optiques". Rennes, INSA, 2005. https://tel.archives-ouvertes.fr/tel-00011186.
Pełny tekst źródłaThis thesis deals with the study of InAs quantum dots (QDs) growth on InP(113)B, for laser applications around the 1. 55 µm optical communication wavelength. QDs are formed in Stransky-Krastanow growth mode by molecular beam epitaxy. The main QD changes with the growth parameters reported in literature are briefly reviewed for InAs/GaAs and InAs/P and the experimental trends are discussed in the frame of nucleation/growth models. Then, structural and optical properties of QDs formed on InP(113)B are studied for different growth parameters. A reduction of the arsenic pressure during QD growth leads to a dramatic increase of the density, up to 1. 6 1011cm-2, along with a reduction of the size dispersion. In a other part, we develop a new capping procedure in two steps, named "quaternary Double Cap procedure" (qDC), to control the emission wavelength. This procedure allows also a reduction of height dispersion and a narrowing photoluminescence linewidth to 40 meV. We optimize the QD stacking in order to improve laser performances. At high density, QD present very good vertical and lateral ordering and low size dispersion. Laser structures grown using the qDC procedure show lasing effect at room temperature. Lasers elaborated with low arsenic flux QDs present improved performances. In particular, a record low threshold current density of 190 A/cm2 is achieved
Rosales, Ricardo. "InAs/InP quantum dash mode locked lasers for optical communications". Phd thesis, Institut National des Télécommunications, 2012. http://tel.archives-ouvertes.fr/tel-00923176.
Pełny tekst źródłaAmniat-Talab, Mahdi. "Préparation d'états quantiques dans les systèmes cavité-atome-laser par passage adiabatique : états multi-photoniques et intrication". Dijon, 2005. http://www.theses.fr/2005DIJOS006.
Pełny tekst źródłaVirte, Martin. "Two-mode dynamics and switching in quantum dot lasers". Thesis, Supélec, 2014. http://www.theses.fr/2014SUPL0020/document.
Pełny tekst źródłaIn this thesis, I study the nonlinear dynamics induced by the competition between two modes in quantum dot laser systems.First, I focus on the competition between polarization modes that takes place in quantum dot vertical-cavity surface-emitting lasers (VCSELs). It is well-known that these devices can exhibit polarization instabilities leading to rich dynamical evolution. Recently, a new peculiar random-like hopping between two non-orthogonal elliptically polarized states has been highlighted in QD VCSELs. This behavior shows intriguing features which clearly call for a different interpretation. In this thesis, I show that the dynamical behavior reported experimentally can accurately be reproduced within the spin-flip model (SFM) framework. In particular, I demonstrate and confirm experimentally that the peculiar random-like hoppings are in fact deterministic low-dimensional chaotic fluctuations, i.e. ``Polarization Chaos''. I then make a proof-of-concept demonstration of a high-speed random bit generator based on polarization chaos, hence demonstrating that the chaotic dynamics uncovered is relevant for optical chaos-based applications.Secondly, I investigate the effects of an external optical feedback on quantum dot lasers emitting simultaneously from the ground and the excited states. I bring new light on the impact of optical feedback and the corresponding mechanisms and bifurcations. I highlight theoretically that optical feedback globally favors the ground state emission, but also that it can be used to switch from one mode to the other when changing the feedback rate and/or the time-delay. In addition, I experimentally report switching between the ground and excited states when varying the external cavity length at the micrometer scale, which supports the theoretical predictions
Calvar, Ariane. "Design, engineering and processing of QC Lasers for high frequency modulation". Paris 7, 2013. http://www.theses.fr/2013PA077267.
Pełny tekst źródłaQuantum cascade lasers (QCLs) are unipolar semiconductor lasers based on intersubband transitions that cover a large portion of the mid and far-infrared electromagnetic spectrum. This work focuses on the study of sources emitting in the mid-infrared range. Two main research lines have been followed in this work. The first one involves the design, fabrication and characterization of high performance ridge QC lasers grown by MOCVD. State-of-the-art threshold current density values are reported around 7. 5 and 9 pm, along with improved thermal performances in CW operation thanks to an optimized fabrication process. To get these results, an optimization work has also been carried out on the MOCVD growth conditions based on systematic post-growth characterization of the epitaxial samples to calculate the real band structure and relate it to the measured laser performances. Improved laser performances could be obtained by reducing the losses originating from the active region thanks to a better control of the growth. The other focus of this work is the fabrication of a mid-infrared QC laser monolithically integrated within a microwave microstrip line for high frequency modulation. By merging microwave and semiconductor laser technologies, we have demonstrated a flat frequency response up to 15 GHz for a device operating at 77 K and emitting at 9 pm. Laser performances are preserved and comparable to state-of-the-art devices. Direct modulation of the QCL embedded into microstrip line at the laser round trip frequency at 13. 7 GHz is investigated and injection-locking of the laser modes to an external RF synthesizer is demonstrated over the MHz range
Dontabactouny, Madhoussoudhana. "Lasers à blocage de modes à base de fils et de boîtes quantiques pour les télécommunications optiques". Phd thesis, INSA de Rennes, 2010. http://tel.archives-ouvertes.fr/tel-00630247.
Pełny tekst źródłaRosales, Ricardo. "InAs/InP quantum dash mode locked lasers for optical communications". Electronic Thesis or Diss., Evry, Institut national des télécommunications, 2012. http://www.theses.fr/2012TELE0039.
Pełny tekst źródłaThis PhD thesis focuses on the study of mode locked laser diodes based on novel optimized InAs Quantum Dash structures grown on InP substrates. It covers several important modelling aspects, the clean room processing of single and two section shallow ridge waveguide lasers, characterization of the fabricated devices and the evaluation of their performance in different application scenarios. Systematic characterization experiments and subsequent analyses have allowed to gain a much deeper comprehension of the physical mechanisms related to the mode locking regime in these devices, thus far not completely understood. This has allowed to better control most of the main physical phenomena limiting device performance, resulting in first demonstrations of record peak power, sub-picosecond pulse, low radio frequency linewidth and high repetition frequency mode locked lasers grown on InP substrates, opening the way to a vast number of potential applications in the 1.55 µm telecommunication window
Lacour, Xavier. "Information Quantique par Passage Adiabatique : Portes Quantiques et Décohérence". Phd thesis, Université de Bourgogne, 2007. http://tel.archives-ouvertes.fr/tel-00180890.
Pełny tekst źródłaprocessus adiabatiques permettant l'implémentation de portes logiques
quantiques, les constituants élémentaires des ordinateurs quantiques, par
l'interaction de champs laser impulsionnels avec des atomes. L'utilisation de
techniques adiabatiques permet des implémentations robustes, i.e. insensibles
aux fluctuations des paramètres expérimentaux. Les processus décrits dans cette
thèse ne nécessitent que le contrôle précis des polarisations et des phases
relatives des champs lasers. Ces processus permettent l'implémentation d'un
ensemble universel de portes quantiques, autorisant l'implémentation de toute
autre porte quantique par combinaisons.
La seconde partie de cette thèse concerne les effets de la décohérence par
déphasage sur le passage adiabatique. La formule de probabilité de transition
d'un système à deux niveaux tenant compte de ces effets décohérents est établie.
Cette formule est valable dans les différents régimes, diabatique et
adiabatique, et permet d'établir les paramètres de trajectoires elliptiques
optimisant le transfert de population.
Huang, Heming. "Optical nonlinearities in quantum dot lasers for high-speed communications". Electronic Thesis or Diss., Paris, ENST, 2017. http://www.theses.fr/2017ENST0012.
Pełny tekst źródłaThe recent evolution of optical communication systems is such that the transfer of massive amounts of information is no longer limited to long-distance transoceanic links or backbone networks. Numerous short-reach applications requiring high data throughputs are emerging, not only in access networks, where upgrades of the bit rate of fiber-to-the-home systems need to be anticipated, but also in data center networks where huge amounts of information may need to be exchanged between servers, in part triggered by the rise of big data applications. The new requirements in terms of cost and energy consumption set by novel short-reach applications therefore need to be considered in the design and operation of a new generation of semiconductor laser sources. Owing to the tight quantum confinement of carriers, quantum dot lasers constitute a class of oscillators exhibiting superior characteristics such as a lower operating threshold, a better thermal stability as well as larger optical nonlinearities. The investigation of quantum dot lasers operating under external perturbations allows probing such optical nonlinearities in the view of developing all-optical wavelength-converters with improved performance as well as optical feedback-resistant transmitters. This last point iseven more critical since it is expected that short-reach links making use of directly modulated sources will experience massive deployment in the near future, in contrast to conventional backbone links where the number of required optoelectronic interfaces remains relatively modest. In order to do so, the thesis reports on novel findings in GaAs- and InP-based quantum dot lasers such as improved bandwidth and conversion efficiency under optical injection and various complex dynamics with delayed quantum dot oscillators emitting on different lasing states. Last but not the least, the massive deployment of coherent systems as well as the realization of future chip-scale atomic clocks require the implementation of optical sources with narrow spectral linewidth otherwise the sensitivity to the phase noise of both transmitters and local oscillators can strongly affect the bit error rates at the receiver. This is another objective to be addressed in the thesis where the benefits of the quantum dot technology has allowed to reach a spectral linewidth as low as 160 kHz (100 kHz under optical feedback) which is of paramount importance not only regarding the aforementioned applications
De, Naurois Guy-Maël. "Combinaison monolithique de lasers à cascade quantique par couplage évanescent". Phd thesis, Université Paris Sud - Paris XI, 2012. http://tel.archives-ouvertes.fr/tel-00829111.
Pełny tekst źródłaZhao, Shiyuan. "Noise, Dynamics and Squeezed Light in Quantum Dot and Interband Cascade Lasers". Electronic Thesis or Diss., Institut polytechnique de Paris, 2023. http://www.theses.fr/2023IPPAT044.
Pełny tekst źródłaSemiconductor lasers have become ubiquitous in both scientific research and engineering applications, and their miniaturization has made significant strides since their initial demonstration in 1960. Two prominent advancements in this domain include quantum dot (QD) lasers, which operate in the near-infrared wavelength range, and interband cascade lasers (ICLs), designed for mid-infrared operation. Two prominent advancements in this domain include quantum dot (QD) lasers, which operate in the near-infrared wavelength range, and interband cascade lasers (ICLs), designed for mid-infrared operation. In the current landscape of optoelectronics, photonic integrated circuits (PICs) play a pivotal and far-reaching role. They offer unmatched scalability, reduced weight, cost-effectiveness, and energy efficiency by enabling the fabrication of complete optical systems using versatile building blocks seamlessly integrated onto a single chip. In this context, the direct epitaxial growth of III-V materials on silicon holds promise as a compelling approach for the development of coherent laser sources. QD lasers with their ultimate three-dimensional carrier confinement, high thermal stability, and robust tolerance for epitaxial defects are promising candidates for serving as on-chip laser sources. Additionally, ICLs are also well-suited for integration into silicon, making them ideal for compact chemical sensing systems. Noise considerations are indeed paramount when it comes to assessing the quality and reliability of technologies. Achieving the shot noise limit and the Schawlow-Townes linewidth has long been recognized as significant milestones. To tackle noise issues, a range of noise reduction techniques has been explored, encompassing passive optical feedback within an external cavity and active electronic feedback mechanisms to compensate for injection current fluctuations. However, while feedback systems can mitigate laser noise, they can also introduce more intricate nonlinear dynamics, giving rise to phenomena like periodic oscillation, square-wave oscillation, and chaos. The first part of this thesis involves an in-depth investigation into noise and dynamics in two distinct laser types. QD lasers are found to exhibit a high degree of robustness when exposed to parasitic optical reflections but manifest increased sensitivity to optoelectronic feedback. Conversely, ICLs display a spectrum of dynamic behaviours when subjected to optical feedback. Furthermore, recent advancements in low-noise pumping circuits for lasers have led to the generation of amplitude-squeezed light. This represents a transition from classical noise to quantum noise, opening up new possibilities in the field of laser technology and quantum optics. The second part of this thesis delves into the phenomenon of amplitude squeezing in both QD lasers and ICLs. The findings indicate that both types of lasers can exhibit broadband squeezing bandwidth and a significant level of squeezing. All these outcomes in this study contribute to a deeper comprehension of the characteristics of QD lasers and ICLs, laying the groundwork for the development of high-performance classical and quantum emitters on PICs in the future
Maurin, Isabelle. "Étude du bruit quantique dans les lasers à semi-conducteurs (VCSELs et diodes laser)". Paris 6, 2002. https://tel.archives-ouvertes.fr/tel-00001605.
Pełny tekst źródłaAbabou, Soraya. "Etude des défauts profonds par des méthodes capacitives dans des super-réseaux et puits quantiques GaAs-GaAlAs". Lyon, INSA, 1991. http://www.theses.fr/1991ISAL0022.
Pełny tekst źródłaThe aim of this study is to characterize deep levels in GaAs-GaAlAs super lattices and to determine the band offset of this system by studying a quantum wells which acts as a trap. In the first part of this Work, deep level transient spectroscopy and photo luminescence measurements have been used to characterize DX centres in Si-doped GaAs-AlAs super lattices and Si-doped GaAlAs alloys grown by molecular beam epitaxy. We have shown that the DX centre appears in the AlAs layer with an energy of 0. 42eV, the same as in the GaAlAs alloys. In the GaAs-AlAs super lattices the DX is detected only when the silicon lies in the AlAs barriers. The DX in this case has the lowest state energy relatively to the GaAs conduction band minimum, while the DX in the GaAs layers is resonant with the conduction mini band. It is possible to reduce the DX concentration by a selective doping of the GaAs layers in the super lattice, by limiting the diffusion of the silicon towards the adjacent layers. In the second part, we have characterized the electron emission from a GaAs quantum well confirmed by GaAlAs layers, and from an enlarged quantum well in GaAs-GaAlAs super lattices. We have find a hetero junction band discontinuities in agreement With the value determined by other methods. The deep levels have been characterized in GaAs-GaAlAs super lattices grown by organometallic vapour phase deposition and the shape of the spectra depends on whether the emission takes place towards the mimi band conduction or towards the GaAs or GaAlAs conduction bands
Drachenko, Oleksiy. "Resonance Magnetophonon Inter Sous-Bandes dans les Structures Unipolaires à Cascades Quantiques". Phd thesis, Université Paul Sabatier - Toulouse III, 2004. http://tel.archives-ouvertes.fr/tel-00008037.
Pełny tekst źródłaBelahsene, Sofiane. "Lasers moyen infrarouge innovants pour analyse des hydrocarbures". Thesis, Montpellier 2, 2011. http://www.theses.fr/2011MON20166/document.
Pełny tekst źródłaThe objective of this thesis, conducted as part of the European contract Senshy, was the realization of laser diodes emitting in the mid-infrared range (from 3.0 to 3.4 µm). These devices are to be integrated into detectors and gas analysis systems based on the principle of absorption spectroscopy (TDLAS). for the detection of alkanes (methane, ethane, propane) and of alkenes (acetylene). The quantum well type-I structures were made by molecular epitaxy on GaSb. Despite having excellent performance in the 2 to 3 µm range, GaInAsSb/AlGaAsSb quantum well lasers rapidly show their limits when crossing the 3 µm barrier (the highest wavelength reached with such a device was 3.04 µm under cw operation at 20°C). This situation was all the more regrettable because several gases have their strongest absorption lines in the 3 to 4 µm range: methane, for example, has a peak of absorption at 3.26 µm overhanging a weaker peak at 2.31 µm by a factor 40. By replacing the quaternary AlGaAsSb by the quinary AlGaInAsSb, we have shown that the internal efficiency could be improved and we have obtained threshold current densities at 2.6 , 3.0 and 3,3 µm that could be favourably compared to the previous records at these wavelengths (respectively, 142 A/cm², 255 A/cm² and 827 A/cm²).DFB laser diodes made from the epitaxial structures were operated at room temperature in the continuous wave regime at 3.06 µm with a single-frequency emission (SMSR greater than 30dB) and a threshold current of 54 mA. At 3.3 µm, DFB devices were operated in cw up to 18 ° C with a SMSR > 30 dB and a current threshold of 140 mA. Eventually, these devices were integrated into a gas analysis system and allowed to reach a concentration limit of 100 ppbv of methane, i.e. 17 times less than the concentration of methane in the air
Leymarie, Hélène. "Modélisation de diodes laser à puits quantiques contraints GaInAs émettant dans la gamme des 980 nm". Toulouse 3, 1994. http://www.theses.fr/1994TOU30173.
Pełny tekst źródłaSpitz, Olivier. "Mid-infrared quantum cascade lasers for chaos secure communications". Electronic Thesis or Diss., Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLT054.
Pełny tekst źródłaThe mid-infrared domain is a promising optical domain because it holds two transparency atmospheric windows, as well as the fingerprint of many chemical compounds. Quantum cascade lasers (QCLs) are one of the available sources in this domain and have already been proven useful for spectroscopic applications and free-space communications. The purpose of that dissertation is to go one step further by implementing a secure free-space communication relying on optical chaos and consequently, to give an accurate cartography of non-linear phenomena in quantum cascade lasers. Initial efforts about free-space secure chaotic transmission have been carried out during this Ph.D. thesis with two chaos-synchronized QCLs, which is a pioneer result paving the way for mid-infrared private communications. In order to have a global picture about the non-linear dynamics in QCLs under external optical feedback, we tuned many experimental parameters and this allowed us studying new phenomena in QCLs. We thus found similarities between QCLs and laser diodes when the chaotic dropouts are synchronized with an external modulation, known as the entrainment phenomenon. A cross-polarization reinjection technique led to square-wave emission in the output of the QCL. Eventually, we studied the triggering of rogue waves in QCLs. Rogue waves are a quite common phenomenon in optics (among other domains in science) but they have never been triggered on-demand in semiconductor lasers under external optical feedback before. Further studies will try to avoid such phenomenon in the output of a QCL under external optical feedback since it can disturb the message to be transmitted in a secure communication. All these experimental results allowed a better understanding of the non-linear dynamics of QCLs and will extend the potential applications of this kind of semiconductor lasers, which have currently been restricted to molecular spectroscopy and optical countermeasure systems
Huang, Heming. "Optical nonlinearities in quantum dot lasers for high-speed communications". Thesis, Paris, ENST, 2017. http://www.theses.fr/2017ENST0012/document.
Pełny tekst źródłaThe recent evolution of optical communication systems is such that the transfer of massive amounts of information is no longer limited to long-distance transoceanic links or backbone networks. Numerous short-reach applications requiring high data throughputs are emerging, not only in access networks, where upgrades of the bit rate of fiber-to-the-home systems need to be anticipated, but also in data center networks where huge amounts of information may need to be exchanged between servers, in part triggered by the rise of big data applications. The new requirements in terms of cost and energy consumption set by novel short-reach applications therefore need to be considered in the design and operation of a new generation of semiconductor laser sources. Owing to the tight quantum confinement of carriers, quantum dot lasers constitute a class of oscillators exhibiting superior characteristics such as a lower operating threshold, a better thermal stability as well as larger optical nonlinearities. The investigation of quantum dot lasers operating under external perturbations allows probing such optical nonlinearities in the view of developing all-optical wavelength-converters with improved performance as well as optical feedback-resistant transmitters. This last point iseven more critical since it is expected that short-reach links making use of directly modulated sources will experience massive deployment in the near future, in contrast to conventional backbone links where the number of required optoelectronic interfaces remains relatively modest. In order to do so, the thesis reports on novel findings in GaAs- and InP-based quantum dot lasers such as improved bandwidth and conversion efficiency under optical injection and various complex dynamics with delayed quantum dot oscillators emitting on different lasing states. Last but not the least, the massive deployment of coherent systems as well as the realization of future chip-scale atomic clocks require the implementation of optical sources with narrow spectral linewidth otherwise the sensitivity to the phase noise of both transmitters and local oscillators can strongly affect the bit error rates at the receiver. This is another objective to be addressed in the thesis where the benefits of the quantum dot technology has allowed to reach a spectral linewidth as low as 160 kHz (100 kHz under optical feedback) which is of paramount importance not only regarding the aforementioned applications
Calo, Cosimo. "Quantum dot based mode locked lasers for optical frequency combs". Electronic Thesis or Diss., Evry, Institut national des télécommunications, 2014. http://www.theses.fr/2014TELE0034.
Pełny tekst źródłaOptical frequency combs, generating tens of equally spaced optical carriers from a single laser source, are very attractive for next-generation wavelength division multiplexing (WDM) communication systems. This PhD thesis presents a study on the optical frequency combs generated by mode-locked laser diodes based on low-dimensional semiconductor nanostructures. In this work, the mode-locking performances of single-section Fabry-Pérot lasers based on different material systems are compared on the basis of the optical spectrum width, the timing jitter and pulse generation capabilities. Then, noticing that InAs quantum dashes grown on InP exhibit on average better characteristics than other examined materials, their unique properties in terms of comb stability and pulse chirp are studied in more detail. Laser chirp, in particular, is first investigated by frequency resolved optical gating (FROG) characterizations. Then, chromatic dispersion of the laser material is assessed in order to verify whether it can account for the large chirp values measured by FROG. For that, a high sensitivity optical frequency-domain reflectometry setup is used and its measurement capabilities are extensively studied and validated. Finally, the combs generated by quantum dash mode-locked lasers are successfully employed for high data rate transmissions using direct-detection optical orthogonal frequency division multiplexing. Terabit per second capacities, as well as the low cost of this system architecture, appear to be particularly promising for future datacom applications
El, Gazouli Mohammed Taoufik. "Conception et modélisation de diodes lasers à InAsSb émettant vers 3. 3 [micro]m". Montpellier 2, 2001. http://www.theses.fr/2001MON20127.
Pełny tekst źródłaBengloan, Jean-Yves. "Amélioration des performances des lasers à cascade quantique : étude du confinement optique et des propriétés thermiques". Paris 11, 2005. https://tel.archives-ouvertes.fr/tel-00084018.
Pełny tekst źródłaRoom temperature continuous-wave (CW) operation is the crucial milestone that promotes a semiconductor laser from an object of research to a device for the world of technology. To achieve this, it is important to increase the maximum CW operating temperature, and to decrease the electrical injected power. The work presented in this thesis investigates these two points to enhance the performance of quantum cascade lasers (QCLs) emitting at lambda~9µm. Waveguide optimisation has been performed on GaAs-based QCLs, to reduce their threshold current and to improve their efficiency. Owing to waveguides with AlGaAs or GaInP cladding layers, new record performances have been obtained for these type of lasers. Selective current injection, realised by proton implantation, is used on GaAs-based QCLs to reduce their operating current and to improve their thermal properties. This technology has been experimented on InP-based QCLs. The benefit of a thick electroplated gold layer, deposit on the top of the ridge devices to improve the heat dissipation, has been also studied. The performances of the two QCLs materials are compared and their future development perspectives are discussed
Yao, Jun. "Etude des non-linearites optiques et des effets de capture des porteurs dans les lasers semi-conducteurs a puits quantiques". Paris, ENST, 1994. http://www.theses.fr/1994ENST0003.
Pełny tekst źródłaPERALES, ANTONINA. "Realisation de lasers puits quantiques a emission monomode a 1,55 micron par epitaxie par jets moleculaires utilisant des sources gazeuses". Paris 6, 1991. http://www.theses.fr/1991PA066275.
Pełny tekst źródłaPerona, Arnaud. "Réalisation par MBE et caractérisation physique de diodes lasers à puits quantiques GaInAsSb/AlGaAsSb émettant vers 2. 3 [micro]m". Montpellier 2, 2002. http://www.theses.fr/2002MON20176.
Pełny tekst źródłaCalo, Cosimo. "Quantum dot based mode locked lasers for optical frequency combs". Thesis, Evry, Institut national des télécommunications, 2014. http://www.theses.fr/2014TELE0034/document.
Pełny tekst źródłaOptical frequency combs, generating tens of equally spaced optical carriers from a single laser source, are very attractive for next-generation wavelength division multiplexing (WDM) communication systems. This PhD thesis presents a study on the optical frequency combs generated by mode-locked laser diodes based on low-dimensional semiconductor nanostructures. In this work, the mode-locking performances of single-section Fabry-Pérot lasers based on different material systems are compared on the basis of the optical spectrum width, the timing jitter and pulse generation capabilities. Then, noticing that InAs quantum dashes grown on InP exhibit on average better characteristics than other examined materials, their unique properties in terms of comb stability and pulse chirp are studied in more detail. Laser chirp, in particular, is first investigated by frequency resolved optical gating (FROG) characterizations. Then, chromatic dispersion of the laser material is assessed in order to verify whether it can account for the large chirp values measured by FROG. For that, a high sensitivity optical frequency-domain reflectometry setup is used and its measurement capabilities are extensively studied and validated. Finally, the combs generated by quantum dash mode-locked lasers are successfully employed for high data rate transmissions using direct-detection optical orthogonal frequency division multiplexing. Terabit per second capacities, as well as the low cost of this system architecture, appear to be particularly promising for future datacom applications
Yarekha, Dmitri. "Etude et réalisation de diodes lasers émettant entre 2,2-2,4 [micro]m pour application à l'analyse de gaz". Montpellier 2, 2001. http://www.theses.fr/2001MON20064.
Pełny tekst źródłaAlghoraibi, Ibrahim. "Croissance et nanostructures inAs sur substrats InP pour les applications lasers à 1,55 µm en télécommunications optiques". Rennes, INSA, 2008. http://www.theses.fr/2008ISAR0031.
Pełny tekst źródłaIn recent years, large interest has been devoted to quantum dot and quantum wire lasers. The main motivation of these research works is the expected improvements of the 1,55 µm emitting laser performances. The work reported in this manuscript concerns InAs nanostructures grown on InP substrates by molecular beam epitaxy. Two types of lasers have been studied. They are based respectively on InAs/GaInAsP quantum dash formed on InP(100) and InAs/AlGaInAs quantum dots grown on InP(311)B substrates. After nanostructure formation studies and optimizations, quantum dashes based laser emitting at room temperature with threshold current density of 375 A/cm2 have been achieved on InP (100) substrates. On (311)B substrates, QD lasers working up to 212 K have fabricated. In this laser, a large decrease of the threshold current from 110 to 140 K is observed. Complementary experiments show that the negative T0 regime can be related to a delayed thermalisation of carriers within quantum dot ensemble
Jollivet, Arnaud. "Dispositifs infrarouges à cascade quantique à base de semiconducteurs GaN/AlGaN et ZnO/ZnMgO". Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS058/document.
Pełny tekst źródłaThis manuscript focuses on the study and on the development of semiconductor heterostructures based on GaN and ZnO material. These materials are particularly promising for the development of infrared optoelectronic intersubband devices in particular for quantum cascade devices. These semiconductors own several advantages to design quantum cascade devices such as a large conduction band offset and a large energy of the LO phonon. These properties predict the possibility to develop devices covering a large spectral range from near-infrared to terahertz and offer the possibility to realize terahertz quantum cascade lasers operating at room temperature
Robert, Cédric. "Study of III-V nanostructures on GaP for lasing emission on Si". Thesis, Rennes, INSA, 2013. http://www.theses.fr/2013ISAR1913/document.
Pełny tekst źródłaThis PhD work focuses on the study of III-V semiconductor nanostructures for the development of laser on Si substrate in a pseudomorphic approach. GaP-based alloys and more specifically dilute nitride GaPN-based alloys are expected to guarantee a low density of crystalline defects through a perfect lattice-matched growth. An extended tight-binding model is first presented to deal with the theoretical challenges for the simulation of electronic and optical properties of semiconductor structures grown on GaP or Si substrate. The optical properties of bulk GaPN and GaAsPN alloys are then studied through temperature dependent continuous wave photoluminescence and time-resolved photoluminescence experiments. The potential of GaAsPN/GaP quantum wells as a laser active zone is discussed in the framework of both theoretical simulations (with the tight-binding model) and experimental studies (with temperature dependent and time-resolved photoluminescence). In particular, the N-induced disorder effects are highlighted. The AlGaP alloy is then proposed as a candidate for the cladding layers. A significant refractive index contrast between AlGaP and GaP is measured by spectroscopic ellipsometry which may lead to a good confinement of the optical mode in a laser structure. The issue of band alignment is highlighted. Solutions based on the quaternary GaAsPN alloy are proposed. Finally, the InGaAs/GaP quantum dots are studied as an alternative to GaAsPN/GaP quantum wells for the active zone. The growth of a high quantum dot density and room temperature photoluminescence are achieved. The electronic band structure is studied by time-resolved photoluminescence and pressure dependent photoluminescence as well as tight-binding and k.p simulations. It demonstrates that the ground optical transition involves mainly X-conduction states
Lecourt, Jean-Bernard. "Etude et réalisation de lasers à fibre auto-impulsionnels àbase d'absorbants saturables". Phd thesis, Université de Rouen, 2006. http://tel.archives-ouvertes.fr/tel-00130694.
Pełny tekst źródłaDans une deuxième partie, nous avons réalisé une source laser fonctionnant en régime de verrouillage de modes. Notre laser s'articule autour d'une fibre erbium et d'un absorbant saturable ultra-rapide (~ ps) InGaAs/InP dopé Fer. Dans cette configuration un régime auto-démarrant d'impulsions de durée 700 fs a été démontré grâce à l'utilisation conjointe d'un absorbant saturable et d'effets de polarisation.
La troisième partie de ce travail de thèse a été consacrée à une autre structure non-linéaire ultra-rapide (500 fs) utilisée comme miroir de cavité. Nous avons obtenu des impulsions dont la durée est de 300 fs. Avec la même cavité, un absorbant saturable à base de nanotubes de carbone (NTC) nous a permis d'obtenir un régime de verrouillage de modes présentant une grande stabilité aussi bien en régime de dispersion anormale qu'en régime de dispersion normale. Les performances obtenues sont des impulsions d'énergies supérieures à 150 pJ avec des durées allant de 700 fs (régime anormal) jusqu'à quelques picosecondes (régime normal).
Enfin nous avons réalisé une source laser à fibre à haute énergie fonctionnant en régime déclenché grâce à un absorbant saturable semiconducteur GaAs. Le milieu à gain est une fibre double-gaine dopée ytterbium. Nous avons obtenus des impulsions énergétiques (7 µJ) d'une durée d'environ 1 µs. Ce régime est obtenu sur un domaine d'accord d'environ 30 nm autour de 1,07 µm en restant spatialement monomode.
Naurois, Guy-Maël de. "Combinaison monolithique de lasers à cascade quantique par couplage évanescent". Thesis, Paris 11, 2012. http://www.theses.fr/2012PA112423/document.
Pełny tekst źródłaDuring the last 10 years, the quantum cascade lasers performances in the mid-infrared have been considerably improved: the wall plug efficiency has reached values superior to 20%, with output power up to 5W in continuous wave operation, at room temperature. Those values have been achieved due to the reduction of the temperature sensibility of the lasers, with characteristic temperature T0 reaching 300K. The output power is now limited to the injected power, which is proportional to the gain region size. This thesis reports an innovating solution consisting on beam combining an array of narrow emitters, monolithically. We experimentally demonstrate for the first time devices of up to 32 emitters of 2µm width emitting in phase by evanescent coupling. Moreover, we show record thermal resistance. Those results highlight the possibility to fabricate high power sources (superior to 10 W) in the mid-infrared, with a good beam quality
Loghmari, Zeineb. "Lasers à cascades quantiques InAs / AISb au-delà de 10µm : émission mono-fréquence et génération du THz par différence de fréquences". Thesis, Montpellier, 2019. http://www.theses.fr/2019MONTS088.
Pełny tekst źródłaApplications such as gas spectroscopy or medical imaging require light sources emitting in the mid- and far infrared (10 µm<λ < 28 µm) as well as in the THz (λ > 60µm). High-performance, continuous wave regime (CW) and single-frequency emission components are essential for this type of application. Quantum cascade lasers (QCLs) are the only sources that can cover this wide range of wavelengths thanks to their inter-sub-band transitions. However, the performance of LCQs in this wavelength range is often limited by non-radiative transitions. The latter generate mechanisms such as photon absorption by TO phonons or electron relaxation by LO phonons. As a result, laser emission in CW and at room temperature becomes particularly difficult. The objective of this thesis is the development of InAs/AlSb LCQs above 10 µm for single-frequency emission and THz generation by frequency difference. A key point in this work is the use of the InAs/AlSb material system. Their advantage is based on the low effective mass. It is 0.023m0 for InAs compared to 0.041m0 for InGaAs and 0.067m0 in GaAs.First, the development of LCQ active regions based on InAs/AlSb emitting at 11µm was carried out. This work made it possible to produce single-frequency DFB sources emitting continuously at 295K and which were used in QEPAS spectroscopy for ethylene sensing. This LCQ has also been transferred to Silicon (Si) substrate. He has demonstrated the world's most efficient LCQ grown directly on Si substrate. The wavelength range ≥ 11µm was also explored. First, by using a dielectric waveguide where this study leads to an active region design at 20µm whose performances exceed the state of the art in the world with continuous operation up to 240K. Then, these technologies were also exploited by using metal-metal waveguides. In this part, the limits of this waveguide were tested. This made it possible to produce a dual-frequency DFB CQL with a metal-metal waveguide emitting two wavelengths in the far infrared for the generation of THz by difference frequency. In this context, the non-linearity of this type of active region has been optimized. The extraction of the THz wave was also studied
Bramati, Alberto. "Etude du bruit quantique dans les lasers à semiconducteur et à solide". Phd thesis, Université Pierre et Marie Curie - Paris VI, 1998. http://tel.archives-ouvertes.fr/tel-00011784.
Pełny tekst źródłaMoreau, Gautier. "Contribution à la caractérisation des propriétés optiques de guides planaires à boîtes quantiques InAs/InP(311)B émettant à 1,55 µm". Rennes 1, 2005. http://www.theses.fr/2005REN1E002.
Pełny tekst źródłaGrunberg, Patrick. "Etude de deux filières lasers émettant vers 2 mu m : filière accordée GaInAsSb/GaSb et filière désaccordée InAs/InP". Montpellier 2, 1993. http://www.theses.fr/1993MON20157.
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