Bibliographies thématiques / Phonon angular momentum

Littérature scientifique sur le sujet « Phonon angular momentum »

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Publié le 11 mars 2023

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Articles de revues sur le sujet "Phonon angular momentum"

Yu Hang, Xu Xi-Fang, Niu Qian et Zhang Li-Fa. « Phonon angular momentum and chiral phonons ». Acta Physica Sinica 67, n^o 7 (2018) : 076302. http://dx.doi.org/10.7498/aps.67.20172407.

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Zhu, Zhihan, Wei Gao, Chunyuan Mu et Hongwei Li. « Reversible orbital angular momentum photon–phonon conversion ». Optica 3, n^o 2 (19 février 2016) : 212. http://dx.doi.org/10.1364/optica.3.000212.

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Park, Sungjoon, et Bohm-Jung Yang. « Phonon Angular Momentum Hall Effect ». Nano Letters 20, n^o 10 (21 septembre 2020) : 7694–99. http://dx.doi.org/10.1021/acs.nanolett.0c03220.

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Krstovska, Danica, Eun Sang Choi et Eden Steven. « Giant Angular Nernst Effect in the Organic Metal α-(BEDT-TTF)2KHg(SCN)4 ». Magnetochemistry 9, n^o 1 (10 janvier 2023) : 27. http://dx.doi.org/10.3390/magnetochemistry9010027.

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We have detected a large Nernst effect in the charge density wave state of the multiband organic metal α-(BEDT-TTF)2KHg(SCN)4. We find that apart from the phonon drag effect, the energy relaxation processes that govern the electron–phonon interactions and the momentum relaxation processes that determine the mobility of the q1D charge carriers have a significant role in observing the large Nernst signal in the CDW state in this organic metal. The emphasised momentum relaxation dynamics in the low field CDW state (CDW0) is a clear indicator of the presence of a significant carrier mobility that might be the main source for observation of the largest Nernst signal. The momentum relaxation is absent with increasing angle and magnetic field, i.e., in the high-field CDW state (CDWx) as evident from the much smaller Nernst effect amplitude in this state. In this case, only the phonon drag effect and electron–phonon interactions are contributing to the transverse thermoelectric signal. Our findings advance and change previous observations on the complex properties of this organic metal.

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Todorov, Tchavdar N., Daniel Dundas, Anthony T. Paxton et Andrew P. Horsfield. « Nonconservative current-induced forces : A physical interpretation ». Beilstein Journal of Nanotechnology 2 (27 octobre 2011) : 727–33. http://dx.doi.org/10.3762/bjnano.2.79.

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We give a physical interpretation of the recently demonstrated nonconservative nature of interatomic forces in current-carrying nanostructures. We start from the analytical expression for the curl of these forces, and evaluate it for a point defect in a current-carrying system. We obtain a general definition of the capacity of electrical current flow to exert a nonconservative force, and thus do net work around closed paths, by a formal noninvasive test procedure. Second, we show that the gain in atomic kinetic energy over time, generated by nonconservative current-induced forces, is equivalent to the uncompensated stimulated emission of directional phonons. This connection with electron–phonon interactions quantifies explicitly the intuitive notion that nonconservative forces work by angular momentum transfer.

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Leckron, Kai, Alexander Baral et Hans Christian Schneider. « Exchange scattering on ultrafast timescales in a ferromagnetic two-sublattice system ». Applied Physics Letters 120, n^o 10 (7 mars 2022) : 102407. http://dx.doi.org/10.1063/5.0080379.

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We investigate ultrafast spin dynamics due to exchange, electron–phonon and Elliott–Yafet spin-flip scattering in a model with a simple band structure and ferromagnetically coupled electronic sublattices (or more generally, subsystems). We show that this incoherent model of electronic dynamics leads to sublattice magnetization changes in opposite directions after ultrashort-pulse excitation. This prominent feature on an ultrafast timescale is related to a transfer of energy and angular momentum between the subsystems due to exchange scattering. Our calculations illustrate a possible incoherent mechanism that works in addition to the coherent optically induced spin transfer mechanism.

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KOTA, V. K. B. « EIKONAL SCATTERING IN THE sdg INTERACTING BOSON MODEL : ANALYTICAL RESULTS IN THE SUsdg(3) LIMIT AND THEIR GENERALIZATIONS ». Modern Physics Letters A 08, n^o 11 (10 avril 1993) : 987–96. http://dx.doi.org/10.1142/s0217732393002464.

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General expression for the representation matrix elements in the SU sdg(3) limit of the sdg interacting boson model (sdgIBM) is derived that determine the scattering amplitude in the eikonal approximation for medium energy proton-nucleus scattering when the target nucleus is deformed and it is described by the SU sdg(3) limit. The SU sdg(3) result is generalized to two important situations: (i) when the target nucleus ground band states are described as states arising out of angular momentum projection from a general single Kπ = 0+ intrinsic state in sdg space; (ii) for rotational bands built on one-phonon excitations in sdgIBM.

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Chen, Zhanghui, et Lin-Wang Wang. « Role of initial magnetic disorder : A time-dependent ab initio study of ultrafast demagnetization mechanisms ». Science Advances 5, n^o 6 (juin 2019) : eaau8000. http://dx.doi.org/10.1126/sciadv.aau8000.

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Despite more than 20 years of development, the underlying physics of the laser-induced demagnetization process is still debated. We present a fast, real-time time-dependent density functional theory (rt-TDDFT) algorithm together with the phenomenological atomic Landau-Lifshitz-Gilbert model to investigate this problem. Our Hamiltonian considers noncollinear magnetic moment, spin-orbit coupling (SOC), electron-electron, electron-phonon, and electron-light interactions. The algorithm for time evolution achieves hundreds of times of speedup enabling calculation of large systems. Our simulations yield a demagnetization rate similar to experiments. We found that (i) the angular momentum flow from light to the system is not essential and the spin Zeeman effect is negligible. (ii) The phonon can play a role but is not essential. (iii) The initial spin disorder and the self-consistent update of the electron-electron interaction play dominant roles and enhance the demagnetization to the experimentally observed rate. The spin disorder connects the electronic structure theory with the phenomenological three-temperature model.

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Chen, Zhanghui, Jun-Wei Luo et Lin-Wang Wang. « Revealing angular momentum transfer channels and timescales in the ultrafast demagnetization process of ferromagnetic semiconductors ». Proceedings of the National Academy of Sciences 116, n^o 39 (9 septembre 2019) : 19258–63. http://dx.doi.org/10.1073/pnas.1907246116.

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Ultrafast control of magnetic order by light provides a promising realization for spintronic devices beyond Moore’s Law and has stimulated intense research interest in recent years. Yet, despite 2 decades of debates, the key question of how the spin angular momentum flows on the femtosecond timescale remains open. The lack of direct first-principle methods and pictures for such process exacerbates the issue. Here, we unravel the laser-induced demagnetization mechanism of ferromagnetic semiconductor GaMnAs, using an efficient time-dependent density functional theory approach that enables the direct real-time snapshot of the demagnetization process. Our results show a clear spin-transfer trajectory from the localized Mn-d electrons to itinerant carriers within 20 fs, illustrating the dominant role of sp−d interaction. We find that the total spin of localized electrons and itinerant carriers is not conserved in the presence of spin-orbit coupling (SOC). Immediately after laser excitation, a growing percentage of spin-angular momentum is quickly transferred to the electron orbital via SOC in about 1 ps, then slowly to the lattice via electron–phonon coupling in a few picoseconds, responsible for the 2-stage process observed experimentally. The spin-relaxation time via SOC is about 300 fs for itinerant carriers and about 700 fs for Mn-d electrons. These results provide a quantum-mechanical microscopic picture for the long-standing questions regarding the channels and timescales of spin transfer, as well as the roles of different interactions underlying the GaMnAs demagnetization process.

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Miedema, P. S., M. Beye, R. Könnecke, G. Schiwietz et A. Föhlisch. « The angular- and crystal-momentum transfer through electron–phonon coupling in silicon and silicon-carbide : similarities and differences ». New Journal of Physics 16, n^o 9 (30 septembre 2014) : 093056. http://dx.doi.org/10.1088/1367-2630/16/9/093056.

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Thèses sur le sujet "Phonon angular momentum"

Bistoni, Oliviero. « Intrinsic vibrational angular momentum driven by non-adiabatic effects in non-collinear magnetic systems ». Doctoral thesis, Università degli studi di Trento, 2022. https://hdl.handle.net/11572/328688.

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In absence of external fields, vibrational modes of periodic systems are usually considered as linearly polarized and, as such, they do not carry angular momentum. Our work proves that non-adiabatic effects due to the electron-phonon coupling are time-reversal symmetry breaking interactions for the vibrational field in systems with non-collinear magnetism and large spin-orbit coupling. Since in these systems the deformation potential matrix elements are necessarily complex, a nonzero synthetic gauge field (Berry curvature) arises in the dynamic equations of the ionic motion. As a result, phonon modes are elliptically polarized in the non-adiabatic framework and intrinsic vibrational angular momenta occur even for non-degenerate modes and without external probes. These results are validated by performing fully relativistic ab-initio calculations on two insulating platinum clusters and a metallic manganese compound, with non-collinear magnetism. In both cases, non-adiabatic vibrational modes carry sizeable angular momenta comparable to the orbital electronic ones in itinerant ferromagnets.

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Géneaux, Romain. « Le moment angulaire de la lumière en génération d'harmoniques d'ordre élevé ». Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLS474/document.

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Le moment angulaire est une quantité essentielle pour l'étude d'objets en interaction. Tout comme la matière, un rayonnement porte du moment angulaire. Il se décompose en deux composantes, moment angulaire de spin (MAS) et moment angulaire orbital (MAO). Chacune de ces composantes a des propriétés spécifiques et ont donné lieu à de nombreuses applications en utilisant de la lumière dans le domaine visible et infrarouge. Dans cette thèse, nous nous proposons d'étudier le comportement des deux types de moment angulaire de la lumière dans un processus très non-linéaire appelé génération d'harmoniques d'ordre élevé (GHOE). Dans ce processus physique connu depuis 1987, un laser infrarouge intense est focalisé dans un jet d'atomes ou de molécules, ce qui dans le bon régime d'intensité permet de générer un rayonnement à courte longueur d'onde (domaine extrême ultraviolet) et extrêmement bref (attoseconde, 1 as = 10⁻¹⁸ s). Nous commençons par décrire théoriquement ce processus, ainsi que définir de manière approfondie la notion de moment angulaire de la lumière. Nous étudions ensuite la GHOE à partir d'un faisceau infrarouge portant du MAO, ce qui nous permet d'obtenir une source unique, générant des impulsions lumineuses ultrabrève de moment angulaire orbital contrôlé et de longueur d'onde de l'ordre de 10nm. Nous étudions étudions la GHOE à partir de faisceaux portant du MAS. En utilisant une résonance du gaz de génération, nous parvenons à transmettre ce moment angulaire au rayonnement extrême ultraviolet. Ce rayonnement est ensuite utilisé pour mesurer des dichroïsmes circulaires de photoionisation dans des molécules chirales, mesures auparavant réservées aux sources synchrotrons. Ceci ouvre la voie à des mesures chirotpiques résolues en temps à l'échelle femto/attoseconde
Angular momentum is an ubiquitous quantity in all areas of physics. Just like matter, radiation carries angular momentum. It can be decomposed in two parts, namely the spin angular momentum (SAM) and the orbital angular momentum (OAM). Each one of these components has very specific properties and lead to numerous applications using visible and infrared light. In this thesis, we study the behavior of these two types of light angular momentum in a very non-linear process called high harmonic generation (HHG). In this physical process known since 1987, an intense infrared laser is focused into an atomic or molecular gas jet, which in the right intensity regime allows to generate a radiation which has a short wavelength (extreme ultraviolet domain) and is extremely brief (attosecond, 1 as = 10⁻¹⁸ s).We begin by describing theoretically this process, as well as defining in depth the notion of light angular momentum. We then study HHG from an infrared laser carrying OAM. This allows to obtain an unique light source, generating ultrashort light pulses of controlled orbital angular momentum with a wavelength of the order of 10 nm. We then study GHOE from beams carrying MAS. Using a resonance from the generation gas, we manage to transfer this angular momentum to the emitted extreme ultraviolet radiation. This radiation is finally used to measure photoionisation circular dichroisms in chiral molecules, measurements previously restricted to synchrotron sources. This paves the way towards chiroptic time resolved measurement on a femto/attosecond timescale

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Chang, Yuan-Pin. « Novel probes of angular momentum polarization ». Thesis, University of Oxford, 2010. http://ora.ox.ac.uk/objects/uuid:d3880edf-436a-415e-8a74-6b1c0fd26e65.

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New dynamical applications of quantum beat spectroscopy (QBS) to molecular dynamics are employed to probe the angular momentum polarization effects in photodissociation and molecular collisions. The magnitude and the dynamical behaviour of angular momentum alignment and orientation, two types of polarization, can be measured via QBS technique on a shot-by-shot basis. The first part of this thesis describes the experimental studies of collisional angular momentum depolarization for the electronically excited state radicals in the presence of the collider partners. Depolarization accompanies both inelastic collisions, giving rise to rotational energy transfer (RET), and elastic collisions. Experimental results also have a fairly good agreement with the results of quasi-classical trajectory scattering calculations. Chapter 1 provides the brief theories about the application of the QBS technique and collisional depolarization. Chapter 2 describes the method and instrumentation employed in the experiments of this work. In Chapter 3, the QBS technique is used to measure the total elastic plus elastic depolarization rate constants under thermal conditions for NO(A,v=0) in the presence of He, Ar, N2, and O2. In the case of NO(A) with Ar, and particularly with He, collisional depolarization is significantly smaller than RET, reflecting the weak long-range forces in these systems. In the case of NO(A)+N2/O2, collisional depolarization and RET are comparable, reflecting the relatively strong long-range forces in these systems. In Chapter 4, the QBS technique is used to measure the elastic and inelastic depolarization and total RET rate constants for OH(A,v=0) under thermal conditions in the presence of He and Ar, as well as the total depolarization rate constants under superthermal conditions. In the case of OH(A)+He, elastic depolarization is sensitive to the N rotational state, and inelastic depolarization is strongly dependent on the collision energy. In the case of OH(A)+Ar, elastic depolarization is insensitive to N, and inelastic depolarization is less sensitive to the collision energy, reflecting that the relatively strong long-range force in OH(A)+Ar system. The second part of this thesis describes the experimental studies of photodissociation under thermal conditions. Chapter 5 provides a brief introduction about several polarization parameter formalisms used for photodissociation, and the incorporation of the QBS technique to measure these polarization parameters. In this thesis, most polarization parameters of the molecular photofragments are measured using the LIF method, and the QBS technique is used as a complementary tool to probe these polarization parameters. In Chapter 6, rotational orientation in the OH(X,v=0) photofragments from H2O2 photodissociation using circularly polarized light at 193 nm is observed. Although H2O2 can be excited to both the A and B electronic states by 193 nm, the observed orientation is only related to the A state dynamics. A proposed mechanism about the coupling between a polarized photon and the H2O2 parent rotation is simulated, and the good agreement between the experimental and simulation results further confirms the validity of this mechanism. In Chapter 7, rotational orientation in the NO(X,v) photofragments from NO2 photodissociation using circularly polarized light at 306 nm (v=0,1,2) and at 355 nm (v=0,1) is observed. Two possible mechanisms, the parent molecular rotation and the coherent effect between multiple electronic states, are discussed. NOCl is photodissociated using circularly polarized light at 306 nm, and NO(X,v) rotational distributions (v=0,1) and rotational orientation (v=0) are measured. For the case of NOCl, the generation of orientation is attributed to the coherent effect.

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Luo, Siwei. « Photon Angular Momentum in Semi-classical Physics and Wave Propagation in Moving Medium ». OpenSIUC, 2013. https://opensiuc.lib.siu.edu/theses/1257.

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Photon and atom interaction is considered as resonance between angular momentum and photon's magnetic field. With the similar approach in classical oscillator, the same mathematical method is used to model the process of photon absorption and emission. In addition, Michelson-Morley experiment, Fizeau experiment and Sagnac effect has implications for properties of wave propagation in moving medium. It is proposed for interferometric methods that capable of either measuring angular velocity or measuring velocity.

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Tkachenko, Georgiy. « Optical trapping and manipulation of chiral microspheres controlled by the photon helicity ». Thesis, Bordeaux, 2014. http://www.theses.fr/2014BORD0102/document.

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Exploiter le degré de liberté angulaire de la lumière pour contrôler les forces optiques ouvre une nouvelle voie pour la manipulation optique de systèmes matériels. Dans ce contexte, notre travail porte sur l’interaction lumière-matière en présence de chiralité, qu’elle soit matérielle ou ondulatoire. Expérimentalement, nous avons utilisé des gouttes de cristaux liquides cholestériques interagissant avec un ou plusieurs champs lumineux polarisés circulairement et nous avons apporté une description quantitative de nos observations. Notre principal résultat correspond à la démonstration que la pression de radiation optique peut être contrôlée par l’hélicité du photon. Ce phénomène est ensuite utilisé, d’une part pour faire une démonstration de principe du tri de la chiralité matérielle via une approche optofluidique et d’autre part pour réaliser un piège optique tridimensionnel sensible à la chiralité de l’objet piégé
Exploiting the angular momentum degree of freedom of light to control the mechanical effects that result from light-matter exchanges of linear momentum is an intriguing challenge that may open new routes towards enhanced optical manipulation of material systems. In this context, our work addresses the interplay between the chirality of matter and the chirality of optical fields. Experimentally, this is done by using cholesteric liquid crystal droplets interacting with circularly polarized light and we provide with theoretical developments to quantitatively support our observations. Our main result is the demonstration of optical radiation force controlled by the photon helicity. This phenomenon is then used to demonstrate the optofluidic sorting of material chirality and the helicity-dependent three-dimensional optical trapping of chiral liquid crystal microspheres

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Maccalli, Stefania. « Development and testing of quasi-optical devices for Photon Orbital Angular Momentum manipulation at millimetre wavelengths ». Thesis, University of Manchester, 2014. https://www.research.manchester.ac.uk/portal/en/theses/development-and-testing-of-quasioptical-devices-for-photon-orbital-angular-momentum-manipulation-at-millimetre-wavelengths(91ab3ac8-62c5-4d3a-b063-4d162d3b61a5).html.

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It is well known that light can carry two different kind of angular momentum that together form the total angular momentum of photons. These two forms are the spin orbital angular momentum, associated with the circular polarisation of light, and the orbital angular momentum of light associated with a wavefront tilted with respect to the propagation axis. Any tilted wavefront generates an orbital component of the angular momentum but there are some special cases in which this property becomes particularly interesting. It is the case of optical vortices which form when the waveform is continuously and uniformly tilted to the propagation axis forming a spiral structure.

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Djordjevic, Ivan B. « Integrated Optics Modules Based Proposal for Quantum Information Processing, Teleportation, QKD, and Quantum Error Correction Employing Photon Angular Momentum ». IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, 2016. http://hdl.handle.net/10150/615122.

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To address key challenges for both quantum communication and quantum computing applications in a simultaneous manner, we propose to employ the photon angular momentum approach by invoking the well-known fact that photons carry both the spin angular momentum (SAM) and the orbital angular momentum (OAM). SAM is associated with polarization, while OAM is associated with azimuthal phase dependence of the complex electric field. Given that OAM eigenstates are mutually orthogonal, in principle, an arbitrary number of bits per single photon can be transmitted. The ability to generate/analyze states with different photon angular momentum, by using either holographic or interferometric methods, allows the realization of quantum states in multidimensional Hilbert space. Because OAM states provide an infinite basis state, while SAM states are 2-D only, the OAM can also be used to increase the security for quantum key distribution (QKD) applications and improve computational power for quantum computing applications. The goal of this paper is to describe photon angular momentum based deterministic universal quantum qudit gates, namely, {generalized-X, generalized-Z, generalized-CNOT} qudit gates, and different quantum modules of importance for various applications, including (fault-tolerant) quantum computing, teleportation, QKD, and quantum error correction. For instance, the basic quantum modules for quantum teleportation applications include the generalized-Bell-state generation module and the QFT-module. The basic quantum module for quantum error correction and fault-tolerant computing is the nonbinary syndrome calculator module. The basic module for entanglement assisted QKD is either the generalized-Bell-state generation module or the Weyl-operator-module. The possibility of implementing all these modules in integrated optics is discussed as well. Finally, we provide security analysis of entanglement assisted multidimensional QKD protocols, employing the proposed qudit modules, by taking into account the imperfect generation of OAM modes.

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Chopinaud, Aurélien. « Atomes et vortex optiques : conversion de moments orbitaux de lumière en utilisant la transition à deux photons 5S-5D du rubidium ». Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLS155/document.

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Le moment orbital angulaire (OAM) de la lumière est une grandeur quantifiée associée à la phase d’un vortex optique et est actuellement une des variables explorées pour les technologies quantiques.Dans ce contexte, cette thèse étudie expérimentalement la conversion de vortex optiques par une vapeur de rubidium, via la transition Raman stimulée à deux photons 5S₁/₂ − 5D₅/₂. Quand les atomes sont soumis à deux lasers respectivement à 780 nm et 776 nm, ils génèrent des rayonnements cohérents, infrarouge à 5,23 μm et bleu à 420 nm. On examine le rayonnement bleu lorsque l’un des lasers ou les deux sont des vortex, en particulier des modes de Laguerre-Gauss. Dans une première partie nous montrons que si l’OAM est porté par le laser à 776 nm, alors le rayonnement bleu émis porte un OAM qui respecte l’accord de phase azimutale et de phase de Gouy. Nous montrons aussi que la conversion est efficace sur une grande plage d’OAM allant de -50 à +50, que l’efficacité est gouvernée par le produit des intensités des lasers incidents et que le rayonnement bleu se comporte comme un mode de Laguerre-Gauss pur. Dans une deuxième partie nous montrons qu’il est possible de convertir une superposition de vortex ou une paire de vortex coaxiaux et que l’OAM du rayonnement bleu émis obéit à la règle de somme des OAM incidents. Pour les cas étudiés, nous proposons un modèle de mélange à quatre ondes qui établit les règles de sélection du processus de conversion d’OAM. Ce travail ouvre la voie vers la conversion d’OAM utilisant des transitions vers des niveaux atomiques plus élevés
The orbital angular momentum of light (OAM) is a quantized quantity arising from the azimuthal phase carried by optical vortices and is well-known for quantum technology applications. Its set of values is theoretically infinite.In this context this thesis experimentally study the conversion of optical vortices in a rubidium vapor through the 5S₁/₂ − 5D₅/₂ stimulated Raman transition. When the atoms are illuminated with laser beams at 780 nm and 776 nm they generate two coherent light beams at 5,23 μm and 420 nm. We investigate the blue light when one laser or both are optical vortices, in particular Laguerre-Gaussian modes. In a first part we show that if the laser at 776 nm carries an OAM the blue light is an optical vortex with an OAM which respects azimutal and Gouy phase matchings. We further show that the conversion is efficient on a large set of OAM from -50 to +50, that the efficiency is governed by the product of the input laser intensities and that the blue light behaves like a pure Laguerre-Gaussian mode. In a second part we demonstrate the conversion of a vortex superposition or a pair of coaxial vortices and that the OAM of the emitted light obeys the conservation rule of total OAM. For each studied case we propose a four wave mixing model establishing selection rules for the conversion process. This work opens possibilities towards OAM conversion using higher atomic levels

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Dixon, Mark. « Studies of spin and charge momentum densities using Compton scattering ». Thesis, University of Warwick, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.340475.

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Vitullo, Dashiell. « Propagation of Photons through Optical Fiber : Spin-Orbit Interaction and Nonlinear Phase Modulation ». Thesis, University of Oregon, 2016. http://hdl.handle.net/1794/20708.

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We investigate two medium-facilitated interactions between properties of light upon propagation through optical fiber. The first is interaction between the spin and intrinsic orbital angular momentum in a linear optical medium. This interaction gives rise to fine structure in the longitudinal momenta of fiber modes and manifests in rotational beating effects. We probe those beating effects experimentally in cutback experiments, where small segments are cut from the output of a fiber to probe the evolution of both output polarization and spatial orientation, and find agreement between theoretical predictions and measured behavior. The second is nonlinear optical interaction due to cross- and self-phase modulation between the complex-valued temporal amplitude profile of pump pulses and the amplitude profiles of generated signal and idler pulses in optical fiber photon-pair sources utilizing the four-wave mixing process named modulation instability. We develop a model including the effects of these nonlinear phase modulations (NPM) describing the time-domain wave function of the output biphoton in the low-gain regime. Assuming Gaussian temporal amplitude profiles for the pump pulse, we numerically simulate the structure of the biphoton wave function, in symmetric and asymmetric group velocity matching configurations. Comparing the overlap of the joint temporal amplitudes with and without NPM indicates how good of an approximation neglecting NPM is, and we investigate the effects of NPM on the Schmidt modes. We find that effects of NPM are small on temporally separable sources utilizing symmetric group velocity matching, but appreciably change the state of temporally entangled sources with the same group velocity matching scheme. For sources designed to produce entangled biphotons, our simulations suggest that NPM increases the Schmidt number, which may increase entanglement resource availability with utilization of a phase-sensitive detection scheme. We find that NPM effects on temporally separable sources designed with asymmetric group velocity matching produce non-negligible changes in the state structure. The purity is unaffected at perfect asymmetric group velocity matching, but if the pump is detuned from the correct wavelength, the purity degrades. The largest changes to the state due to NPM occur in long fibers with long pulse durations and low repetition rates.

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Livres sur le sujet "Phonon angular momentum"

Hamada, Masato. Theory of Generation and Conversion of Phonon Angular Momentum. Singapore : Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-33-4690-1.

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1935-, Allen L., Barnett S. M et Padgett Miles J, dir. Optical angular momentum. Bristol : Institute of Physics Pub., 2003.

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Twisted photons : Applications of light with orbital angular momentum. Weinheim, Germany : Wiley-VCH, 2011.

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Hamada, Masato. Theory of Generation and Conversion of Phonon Angular Momentum. Springer Singapore Pte. Limited, 2022.

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Hamada, Masato. Theory of Generation and Conversion of Phonon Angular Momentum. Springer Singapore Pte. Limited, 2021.

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Barnett, Stephen M., L. Allen et Miles J. Padgett. Optical Angular Momentum. Taylor & Francis Group, 2016.

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Barnett, S. M., L. Allen et Miles J. Padgett. Optical Angular Momentum. Taylor & Francis Group, 2020.

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Barnett, Stephen M., L. Allen et Miles J. Padgett. Optical Angular Momentum. Taylor & Francis Group, 2003.

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Barnett, Stephen M., L. Allen et Miles J. Padgett. Optical Angular Momentum. Taylor & Francis Group, 2016.

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Barnett, Stephen, Les Allen et Miles Padgett. Optical Angular Momentum. Taylor & Francis Group, 2010.

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Chapitres de livres sur le sujet "Phonon angular momentum"

Hamada, Masato. « Phonon Thermal Edelstein Effect ». Dans Theory of Generation and Conversion of Phonon Angular Momentum, 29–48. Singapore : Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-33-4690-1_3.

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Hamada, Masato. « Magnetoelectric Effect for Phonons ». Dans Theory of Generation and Conversion of Phonon Angular Momentum, 49–68. Singapore : Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-33-4690-1_4.

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Hamada, Masato. « Background ». Dans Theory of Generation and Conversion of Phonon Angular Momentum, 7–27. Singapore : Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-33-4690-1_2.

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Hamada, Masato. « Introduction ». Dans Theory of Generation and Conversion of Phonon Angular Momentum, 1–5. Singapore : Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-33-4690-1_1.

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Hamada, Masato. « Conclusion ». Dans Theory of Generation and Conversion of Phonon Angular Momentum, 89–91. Singapore : Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-33-4690-1_6.

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Hamada, Masato. « Conversion Between Spins and Mechanical Rotations ». Dans Theory of Generation and Conversion of Phonon Angular Momentum, 69–88. Singapore : Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-33-4690-1_5.

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Keller, Ole. « Photon Angular Momentum ». Dans Quantum Theory of Near-Field Electrodynamics, 333–47. Berlin, Heidelberg : Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-17410-0_17.

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Loke, Vincent L. Y., Theodor Asavei, Simon Parkin, Norman R. Heckenberg, Halina Rubinsztein-Dunlop et Timo A. Nieminen. « Driving Optical Micromachines with Orbital Angular Momentum ». Dans Twisted Photons, 93–115. Weinheim, Germany : Wiley-VCH Verlag GmbH & Co. KGaA, 2011. http://dx.doi.org/10.1002/9783527635368.ch6.

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Allen, Les, et Miles Padgett. « The Orbital Angular Momentum of Light : An Introduction ». Dans Twisted Photons, 1–12. Weinheim, Germany : Wiley-VCH Verlag GmbH & Co. KGaA, 2011. http://dx.doi.org/10.1002/9783527635368.ch1.

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Fickler, Robert. « Entanglement of High Angular Momenta ». Dans Quantum Entanglement of Complex Structures of Photons, 35–59. Cham : Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-22231-8_3.

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Actes de conférences sur le sujet "Phonon angular momentum"

Zhu, Zhihan, Liwen Sheng, Chunyuan Mu et Wei Gao. « Orbital Angular Momentum in Photon-Phonon Coupling ». Dans CLEO : QELS_Fundamental Science. Washington, D.C. : OSA, 2016. http://dx.doi.org/10.1364/cleo_qels.2016.ftu3a.1.

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Nemirovsky-Levy, Liat, Uzi Pereg et Mordechai Segev. « Increasing Communication Rates Using Photonic Hyperentangled States ». Dans Frontiers in Optics. Washington, D.C. : Optica Publishing Group, 2022. http://dx.doi.org/10.1364/fio.2022.jtu5a.41.

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We propose a mechanism for increasing transmission rate of quantum communication channels, by multiplexing spin and multiple orbital angular momentum states on a single photon, transmitting the photon, and demultiplexing them to different photons.

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Djordjevic, Ivan B., et Yequn Zhang. « Photon angular momentum based multidimensional quantum key distribution ». Dans 2014 16th International Conference on Transparent Optical Networks (ICTON). IEEE, 2014. http://dx.doi.org/10.1109/icton.2014.6876370.

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Tauchert, S. R., M. Volkov, D. Ehberger, D. Kazenwadel, M. Evers, H. Lange, A. Donges et al. « Polarized Phonons Carry Angular Momentum in Ultrafast Demagnetization ». Dans International Conference on Ultrafast Phenomena. Washington, D.C. : Optica Publishing Group, 2022. http://dx.doi.org/10.1364/up.2022.tu2a.1.

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Elias, Nicholas M. « Primum Non Torquere∗ - Photon Orbital Angular Momentum in Astronomy ». Dans Propagation Through and Characterization of Distributed Volume Turbulence. Washington, D.C. : OSA, 2013. http://dx.doi.org/10.1364/pcdvt.2013.ptu3f.1.

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Franke-Arnold, Sonja. « Orbital angular momentum of photons, atoms, and electrons ». Dans SPIE OPTO, sous la direction de Jesper Glückstad, David L. Andrews et Enrique J. Galvez. SPIE, 2013. http://dx.doi.org/10.1117/12.2002984.

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Tang, Ruikai, Xiongjie Li, Wenjie Wu, Haifeng Pan, Heping Zeng et E. Wu. « Quantum information interface for orbital angular momentum photons ». Dans CLEO : Applications and Technology. Washington, D.C. : OSA, 2015. http://dx.doi.org/10.1364/cleo_at.2015.jw2a.5.

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Li, Yongnan, Ling-Jun Kong, Zhi-Cheng Ren, Chenghou Tu et Hui-Tian Wang. « Trajectory-based unveiling of angular momentum of photons ». Dans Frontiers in Optics. Washington, D.C. : OSA, 2014. http://dx.doi.org/10.1364/fio.2014.ftu1c.5.

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Liu, Xiao, Dong Beom Kim, Virginia O. Lorenz et Siddharth Ramachandran. « Shaping Biphoton Spectral Correlations with Orbital Angular Momentum Fiber Modes ». Dans Quantum 2.0. Washington, D.C. : Optica Publishing Group, 2022. http://dx.doi.org/10.1364/quantum.2022.qth4b.1.

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We leverage large channel-count optical fibers supporting orbital angular momentum (OAM) modes to show that near-infrared to telecom photon pairs can be engineered to have arbitrary correlations by choice of mode combinations.

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Jha, A. K., B. Jack, E. Yao, J. Leach, R. W. Boyd, G. S. Buller, S. M. Barnett, S. Franke-Arnold et M. J. Padgett. « Fourier Relationship Between Angular Position and Orbital Angular Momentum of Entangled Photons ». Dans Laser Science. Washington, D.C. : OSA, 2008. http://dx.doi.org/10.1364/ls.2008.lthe2.

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