Littérature scientifique sur le sujet « Electric dipolar interactions »
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Articles de revues sur le sujet "Electric dipolar interactions"
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Andreev, Pavel A. « Simultaneous dipole and quadrupole moment contribution in the Bogoliubov spectrum : Application of the non-integral Gross–Pitaevskii equation ». Modern Physics Letters B 31, no 13 (10 mai 2017) : 1750152. http://dx.doi.org/10.1142/s0217984917501524.
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We present the Gross–Pitaevskii equation for Bose–Einstein condensates (BECs) possessing the electric dipole and the electric quadrupole moments in a non-integral form. These equations are coupled with the Maxwell equations. The model under consideration includes the dipole–dipole, the dipole–quadrupole, and the quadrupole–quadrupole interactions in terms of the electric field created by the dipoles and quadrupoles. We apply this model to obtain the Bogoliubov spectrum for three-dimensional BECs with a repulsive short-range interaction. We obtain an extra term in the Bogoliubov spectrum in comparison with the dipolar BECs. We show that the quadrupole–quadrupole interaction gives a positive contribution in the Bogoliubov spectrum. Hence, this spectrum is stable.
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Khalyavin, Dmitry D., Roger D. Johnson, Fabio Orlandi, Paolo G. Radaelli, Pascal Manuel et Alexei A. Belik. « Emergent helical texture of electric dipoles ». Science 369, no 6504 (6 août 2020) : 680–84. http://dx.doi.org/10.1126/science.aay7356.
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Long-range ordering of magnetic dipoles in bulk materials gives rise to a broad range of magnetic structures, from simple collinear ferromagnets and antiferromagnets, to complex magnetic helicoidal textures stabilized by competing exchange interactions. In contrast, dipolar order in dielectric crystals is typically limited to parallel (ferroelectric) and antiparallel (antiferroelectric) collinear alignments of electric dipoles. Here, we report an observation of incommensurate helical ordering of electric dipoles by light hole doping of the quadruple perovskite BiMn7O12. In analogy with magnetism, the electric dipole helicoidal texture is stabilized by competing instabilities. Specifically, orbital ordering and lone electron pair stereochemical activity compete, giving rise to phase transitions from a nonchiral cubic structure to an incommensurate electric dipole and orbital helix via an intermediate density wave.
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Kusmartsev, F. V., et M. Saarela. « Dipolar clusters and ferroelectricity in high Tc superconductors ». International Journal of Modern Physics B 29, no 25n26 (14 octobre 2015) : 1542002. http://dx.doi.org/10.1142/s0217979215420023.
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In this paper, we show that doping of hole charge carriers induces formation of resonance plaquettes (RPs) having electric dipolar moments and fluctuating stripes in cuprates. A single RP is created by many-body interactions between the dopant ion or a charge fluctuation outside and holes inside the CuO plane. In such a process, Coulomb interacting holes in the CuO plane are self-organized into four-particles resonance valence bond plaquettes bound with dopants or polarons located in the spacer layer between CuO planes. Such RPs have ordered and disordered phases. They are ordered into charge density waves (CDW) or stripes only at certain conditions. The lowest energy of the ordered phase corresponds to a local antiferroelectric ordering. The RPs mobility is very low at low temperatures and they are bound into dipole–dipole pairs. Electromagnetic radiation interacts strongly with RPs electric dipoles and when the sample is subjected to it, the mobility changes significantly. This leads to a fractal growth of dipolar RP clusters. The existence of electric dipoles and CDW reveal a series of new phenomena such as ferroelectricity, strong light and microwave absorption and the field induced superconductivity.
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Chan, Chin Han, et Hans-Werner Kammer. « Characterization of polymer electrolytes by dielectric response using electrochemical impedance spectroscopy ». Pure and Applied Chemistry 90, no 6 (27 juin 2018) : 939–53. http://dx.doi.org/10.1515/pac-2017-0911.
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Abstract Authors present a phenomenological view on dielectric relaxation in polymer electrolytes, which is monitored by electrochemical impedance spectroscopy. Molecular interaction of polymer chains with salt molecules (or dipole-dipole interaction between segments and salt molecules) leads to dipolar molecular entities. Frequency-dependant impedance spectra are the key quantities of the interest for determination of electric properties of materials and their interfaces with conducting electrodes. Salt concentration serves as parameter. Bulk and interfacial properties of the samples are discussed in terms of impedance (Z*) and modulus (M*) spectra. We focus on two different classes of systems, i.e. high molar mass of poly(ethylene oxide) (PEO)+lithium perchlorate (LiClO4) (i.e. the inorganic salt) and epoxidized natural rubber (ENR-25) with 25 mol% of epoxide content+LiClO4. Impedance spectra with salt content as parameter tell us that we have interaction between dipolar entities leading to dispersion of relaxation times. However, as scaling relations show, dispersion of relaxation times does not depend on salt content in the PEO system. The relaxation peak for the imaginary part of electric modulus (M″) provides information on long-range motion of dipoles. Summarizing the results from imaginary part of impedance spectrum (Z″), tan δ (imaginary/real of permittivities) and M″ for the two systems under the discussion, PEO behaves like a mixture of chains with dipoles. There are interactions between the dipoles, but they are relaxing individually. Therefore, we see PEO-salt system as a polymer electrolyte where only a tiny fraction of added salt molecules becomes electrically active in promoting conductance. However, ENR-25-salt system behaves just as a macroscopic dipole and it can not display electrode polarization or electric relaxation because there is no mobility of individual dipoles. Hence, ENR-25-salt does not form a polymer electrolyte in the classic sense.
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Tobias, William G., Kyle Matsuda, Jun-Ru Li, Calder Miller, Annette N. Carroll, Thomas Bilitewski, Ana Maria Rey et Jun Ye. « Reactions between layer-resolved molecules mediated by dipolar spin exchange ». Science 375, no 6586 (18 mars 2022) : 1299–303. http://dx.doi.org/10.1126/science.abn8525.
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Microscopic control over polar molecules with tunable interactions enables the realization of distinct quantum phenomena. Using an electric field gradient, we demonstrated layer-resolved state preparation and imaging of ultracold potassium-rubidium molecules confined to two-dimensional planes in an optical lattice. The rotational coherence was maximized by rotating the electric field relative to the light polarization for state-insensitive trapping. Spatially separated molecules in adjacent layers interact through dipolar spin exchange of rotational angular momentum; by adjusting these interactions, we regulated the local chemical reaction rate. The resonance width of the exchange process vastly exceeded the dipolar interaction energy, an effect attributed to thermal energy. This work realized precise control of interacting molecules, enabling electric field microscopy on subwavelength scales and allowing access to unexplored physics in two-dimensional systems.
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Rosenberg, Itamar, Dror Liran, Yotam Mazuz-Harpaz, Kenneth West, Loren Pfeiffer et Ronen Rapaport. « Strongly interacting dipolar-polaritons ». Science Advances 4, no 10 (octobre 2018) : eaat8880. http://dx.doi.org/10.1126/sciadv.aat8880.
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Exciton-polaritons are mutually interacting quantum hybridizations of confined photons and electronic excitations. Here, we demonstrate a system of optically guided, electrically polarized exciton-polaritons (“dipolaritons”) that displays up to 200-fold enhancement of the polariton-polariton interaction strength compared to unpolarized polaritons. The magnitude of the dipolar interaction enhancement can be turned on and off and can be easily tuned over a very wide range by varying the applied polarizing electric field. The large interaction strengths and the very long propagation distances of these fully guided dipolaritons open up new opportunities for realizing complex quantum circuitry and quantum simulators, as well as topological states based on exciton-polaritons, for which the interactions between polaritons need to be large and spatially or temporally controlled. The results also raise fundamental questions on the origin of these large enhancements.
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Shih, Chunyu, John J. Molina et Ryoichi Yamamoto. « Field-induced dipolar attraction between like-charged colloids ». Soft Matter 14, no 22 (2018) : 4520–29. http://dx.doi.org/10.1039/c8sm00395e.
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The field induced anisotropic interactions between like-charged colloidal particles is studied using direct numerical simulations, where the polarization of the electric double layer is explicitly computed under external AC electric fields.
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Peshkovsky, Alexey, et Ann E. McDermott. « Dipolar Interactions in Molecules Aligned by Strong AC Electric Fields ». Journal of Magnetic Resonance 147, no 1 (novembre 2000) : 104–9. http://dx.doi.org/10.1006/jmre.2000.2167.
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Guerrero, Tomás, Rosa Santillan, Héctor García-Ortega, Omar G. Morales-Saavedra, Norberto Farfán et Pascal G. Lacroix. « Bis(4-nitroanilines) in interactions through a π-conjugated bridge : conformational effects and potential molecular switches ». New Journal of Chemistry 41, no 20 (2017) : 11881–90. http://dx.doi.org/10.1039/c7nj02622f.
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Freeman, G. R., L. D. Coulson et N. H. March. « On the Ehrenberg–Siday–Aharonov–Bohm (ESAB) and Aharonov–Casher (AC) Effects ». Modern Physics Letters B 12, no 22 (20 septembre 1998) : 933–42. http://dx.doi.org/10.1142/s0217984998001086.
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When an electron beam passes outside a confined magnetic flux, the motional magnetic field of the electrons overlaps the confined flux. The potential energy of the magnetic dipolar interaction of the motional magnetic field with the confined magnetic flux causes the velocity of the electrons to change slightly, which shifts the phase of the electron de Broglie wave. When portions of an electron beam pass on different sides of a confined flux and are then mixed, they produce an interference pattern. There is a similar magnetic dipolar interaction, with resulting velocity and phase changes, when a beam of magnetic particles interacts with the motional magnetic flux produced by their crossing a strong electric field. These are classical electromagnetic dipolar (not Lorentz) interactions that causes changes in Berry's geometrical phase, but are not ESAB or AC effects. Data that were suggested to demonstrate the ESAB and AC effects have been quantitatively interpreted in terms of motional magnetic fields and velocity changes.
Thèses sur le sujet "Electric dipolar interactions"
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Hernández, Jesús V. Robicheaux Francis J. « Many-body dipole interactions ». Auburn, Ala, 2008. http://repo.lib.auburn.edu/EtdRoot/2008/SUMMER/Physics/Dissertation/Hernandez_Jesus_41.pdf.
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Karam, Charbel. « Optical shielding of collisions between ultracold polar molecules ». Electronic Thesis or Diss., université Paris-Saclay, 2024. http://www.theses.fr/2024UPASP137.
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Ce travail s'inscrit dans le contexte des recherches sur les gaz quantiques de molécules ultra-froides. Ce domaine en pleine expansion place ce type de système comme plate-forme prometteuse pour le contrôle de gaz quantiques pour des applications comme la simulation quantique ou la chimie ultra-froide.Lorsque ces molécules sont préparées dans leur état fondamental absolu et piégées, les observations révèlent la fuite rapide des molécules du piège par des processus collisionnels encore mal compris, empêchant toute application. Une solution consiste à exposer ces molécules à un champ électromagnétique pour supprimer ces pertes, en écrantant les collisions entre molécules. L'écrantage consiste à transformer les interactions attractives en interactions répulsives.Dans cette thèse, je propose une nouvelle technique d'écrantage des collisions basée sur un processus à deux photons dans le domaine optique. La principale motivation pour cette méthode est de combiner les avantages des techniques existantes dans le domaine microonde, tout en éliminant leurs limitations.Je commence par explorer et modéliser les interactions à longue portée entre les molécules polaires, dominées par l'interaction dipôle-dipôle. Je présente mes calculs des courbes d'énergie potentielle d'interaction à longue portée entre deux molécules dans leur état électronique fondamental ainsi que dans des états électroniques excités. Ce calcul, effectué dans la base couplée des moments angulaires dans le référentiel du laboratoire, a permis d'identifier des configurations où l'interaction entre les molécules est répulsive.Il convient donc de coupler l'état initial attractif des molécules en collision, à cet état répulsif. J'ai modélisé l'interaction entre deux molécules dans un schéma de type Raman à deux photons. A l'infini, les molécules individuelles sont placées dans les conditions de la transparence électromagnétiquement induite (EIT), pour les protéger de la diffusion de photons, qui contribue au réchauffement du gaz quantique.Lorsque les molécules interagissent, j'ai montré que leur exposition aux deux photons se modélise au travers d'un schéma à 5 niveaux, chacun d'entre eux étant composé de multiples composantes. Cela impose la prise en compte de cette complexité intrinsèque pour une représentation fidèle du comportement des molécules, s'éloignant ainsi des modèles connus à petit nombre de niveaux. Les fréquences de Rabi et le décalage en fréquence des deux lasers permettent de contrôler l'évolution de la collision entre molécules. En appliquant la théorie de la diffusion indépendante du temps, j'ai propagé la fonction d'onde des deux molécules, dont l'interaction est décrite par les courbes de potentiel habillées par la lumière, en considérant un formalisme purement quantique. J'ai calculé les taux de collisions élastiques, inélastiques et réactives induites par les lasers. L'objectif a été de déterminer les conditions pour lesquelles le taux de collisions élastiques domine les taux de collisions inélastiques et réactives, traduisant les pertes observées. Pour des valeurs de fréquence de Rabi et de décalage en fréquence compatibles avec les conditions expérimentales typiques, le taux de collisions élastiques demeure inférieur aux autres taux, ce qui empêche un écrantage efficace, tout en démontrant l'influence réelle des lasers. La principale raison de cette efficacité limitée est que le schéma proposé repose sur des interactions dipôle-dipôle du 2ème ordre, qui ne sont pas suffisamment fortes pour induire des couplages assez intenses pour protéger les molécules des pertes.Pour y remédier, nous proposons d'utiliser un faible champ électrique statique, qui pourrait coupler des états au 1er ordre, induisant des interactions dipôle-dipôle plus fortes et donc un écrantage plus efficace. Un tel champ est nécessaire dans les futures expériences visant à étudier les effets anisotropes dans les gaz quantiques moléculaires ultra-froidsThis work is part of the ongoing research into quantum gases of ultracold molecules. This rapidly expanding field positions these systems as promising platforms for the complete control of quantum gases for applications such as quantum simulation or ultracold chemistry.When these molecules are prepared in their absolute ground state and trapped, observations reveal the rapid escape of molecules from the trap due to collision processes that are still not fully understood, preventing any applications. One solution is to expose these molecules to an electromagnetic field to suppress these losses by "shielding" collisions between molecules. Shielding involves transforming attractive interactions into repulsive ones.In this thesis, I propose a new technique for collision shielding based on a two-photon process in the optical domain. The main motivation for this method is to combine the advantages of existing techniques in the microwave domain while eliminating their limitations.I begin by exploring and modeling long-range interactions between polar molecules, dominated by dipole-dipole interactions. I present my calculations of the potential energy curves of long-range interactions between two molecules in their electronic ground state as well as in electronically excited states. This calculation, carried out in the coupled angular momentum basis in the laboratory frame, allowed me to identify configurations where the interaction between the molecules is repulsive.Thus, it is necessary to couple the attractive initial state of the colliding molecules to this repulsive state. I modeled the interaction between two molecules in a two-photon Raman-type scheme within the dipole approximation. At infinity, the individual molecules are placed in conditions of electromagnetically induced transparency (EIT), to protect them from photon scattering, which contributes to the heating of the quantum gas.When the molecules interact, I showed that their exposure to the two photons is modeled through a 5-level scheme, each of which is composed of multiple components. This imposes the need to consider this intrinsic complexity for a faithful representation of the molecules' behavior, departing from known small-level models. The Rabi frequencies and the detuning of the two lasers allow control over the evolution of the collision between molecules.By applying time-independent scattering theory, I propagated the wave function of the two molecules, whose interaction is described by the light-dressed potential curves, using a purely quantum formalism. I calculated the elastic, inelastic, and reactive collision rates induced by the lasers.My goal was to determine the conditions under which the elastic collision rate dominates the inelastic and reactive collision rates, which account for the observed losses. For Rabi frequency and detuning values compatible with typical experimental conditions, the elastic collision rate remains lower than the other rates, preventing effective shielding, though still demonstrating the real influence of the lasers. The main reason for this limited effectiveness is that the proposed scheme relies on second-order dipole-dipole interactions, which are not strong enough to induce sufficiently intense couplings to protect the molecules from losses.To address this issue, we propose using a weak static electric field, which could couple states at the first order, inducing stronger dipole-dipole interactions and thereby more effective shielding. Such a field is necessary for future experiments aiming to study anisotropic effects in quantum gases of ultracold molecules
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Zhang, Yuan. « STM Investigation of Electric Polar Molecular Self-Assembly and Artificial Electric Polar Molecular Rotors ». Ohio University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1416927903.
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Afrousheh, Kourosh. « Observation of Resonant Electric Dipole-Dipole Interactions Between Cold Rydberg Atoms Using Microwave Spectroscopy ». Thesis, University of Waterloo, 2006. http://hdl.handle.net/10012/2970.
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This thesis reports the first observation of the resonant electric dipole-dipole interaction between cold Rydberg atoms using microwave spectroscopy, the observation of the magnetic field suppression of resonant interactions, and the development of a unique technique for precise magnetic field measurements. A Rydberg state 46d5/2 of laser cooled 85Rb atoms has been optically excited. A fraction of these atoms has been transferred to another Rydberg state 47p3/2 or 45f5/2,7/2 to introduce resonant electric dipole-dipole interactions. The line broadening of the two-photon 46d5/2-47d5/2 microwave transition due to the interaction of 46d5/2 with 47p3/2 or 45f5/2,7/2 atoms has been used as a probe of the interatomic interactions. This experiment has been repeated with a DC magnetic field applied. The application of a weak magnetic field (≤0. 6G) has reduced the line broadening due to the resonant electric dipole-dipole interaction, indicating that the interactions are suppressed by the field. Theoretical models have been developed that predict the energy shifts due to the resonant electric dipole-dipole interaction, and the suppression of interactions by magnetic fields. A novel technique for sensitive measurement of magnetic fields using the 34s1/2-34p1/2 one-photon microwave transition has also been presented. Using this technique, it has been possible to calibrate magnetic fields in the magneto-optical trap (MOT) apparatus to less than 10mG, and put an upper bound of 17mG on any remaining field inhomogeneity.
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Parsa, Nitin. « Non Linear Interaction of Microwaves with Ferroelectric Materials ». University of Akron / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=akron1451999954.
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Ilyas, Nahid. « From Growth to Electronic Structure of Dipolar Organic Semiconductors on Coinage Metal Surfaces ». Diss., The University of Arizona, 2014. http://hdl.handle.net/10150/321297.
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In this thesis, I present a comprehensive study of the interfacial electronic structure and thin film growth of two types of dipolar organic semiconductors on noble metals by employing a surface science approach, which underlines the critical role of surface electronic states in determining the interfacial electronic structure and self-assembly of organic semiconductors. I show that the electronic structure at organic/metal interfaces is complex and depends on important factors such as molecular adsorption configuration, surface/molecule coupling strength, reactivity of the substrate, molecular electrostatics, and local film structure. I demonstrate the fundamental capability of the image potential states and resonances in probing the local film environment, especially in systems consisting of inhomogeneous film structure. I also show that the presence of adsorbates on a surface allows one to investigate quantum mechanical interference effects otherwise not accessible on the bare surface. The dipolar organic semiconductors studied here are vanadyl naphthalocyanine (VONc) and chloroboron-subphthalocyanine (ClB-SubPc). The single crystals of gold and copper with hexagonal surface symmetry (111) were used to investigate the interfacial properties of VONc and ClB-SubPc, respectively. The fundamental understanding of self-assembly of large π-conjugated organic semiconductors on metals is a crucial step in controlling fabrication of supramolecular structures. Here, I provide a first step in this direction with a detailed and quantitative analysis of molecular nearest-neighbor distances that unravels the fundamental intermolecular interactions of organic semiconductors on transition metal surfaces. I additionally investigated the interfacial electronic structure of these organic semiconductors to examine the relation between molecular adsorption orientation and charge transfer across the interface.
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Alcantara, Ortigoza Marisol. « Theoretical studies of electronic, vibrational, and magnetic properties of chemisorbed surfaces and nanoalloys ». Diss., Manhattan, Kan. : Kansas State University, 2007. http://hdl.handle.net/2097/496.
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Napolitano, Lia Munhoz Benati. « Estudo através da técnica de ressonância paramagnética eletrônica, em bandas X e Q, dos compostos dinucleares Cu2(TzTs)4 e [Cu(flu)2DMF]2 ». Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/76/76132/tde-24032010-171758/.
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Esta tese relata um estudo pormenorizado, efetuado através da técnica de Ressonância Paramagnética Eletrônica (RPE) em bandas X (~ 9.5 GHz) e Q (~ 34.5 GHz), de amostras nas formas cristalina e pulverizada dos compostos dinucleares Cu2(TzTs)4, C40H36Cu2N8O8S8, e [Cu(flu)2DMF]2, C62H50Cu2F12N6O10. Tratamentos meticulosos dos espectros de RPE pertinentes a tais compostos propiciaram determinar tanto o parâmetro de interação antiferromagnética, J0, entre pares de íons Cu(II) existentes em uma unidade dinuclear (Hex = J0 S1·S2) como também os valores principais alusivos às matrizes g e D; onde a primeira refere-se à interação Zeeman [Hz = BB0(g1·S1 + g2·S2)] e a última reporta as interações spin-spin anisotrópicas (Hani = S1·D·S2) entre pares de íons Cu(II) presentes em uma unidade dinuclear. Ademais, medidas de RPE realizadas com um monocristal do composto Cu2(TzTs)4 permitiram detectar e estimar, no contexto interdinuclear, o fraco acoplamento de exchange, |J\'| = (0.060 ± 0.015) cm-1, existente entre unidades dinucleares vizinhas: este acoplamento existente entre uma unidade dinuclear e o meio randômico constituído pelas unidades dinucleares vizinhas conduz à decoerência (i.e. uma transição de fase quântica que colapsa a interação dipolar quando a magnitude do acoplamento de exchange isotrópico entre as unidades dinucleares vizinhas iguala-se à magnitude do acoplamento dipolar intradinuclear). No âmbito concernente ao composto [Cu(flu)2DMF]2, foi possível simular acuradamente as sete linhas de ressonância características do desdobramento hiperfino advindo de n = 2 núcleos equivalentes de centros paramagnéticos Cu2+ (I = 3/2) e, por conseguinte, os valores principais pertinentes à matriz de interação hiperfina A (Hhyper = S1·A·I1 + S2·A·I2) puderam ser precisamente determinados.We report detailed Electron Paramagnetic Resonance (EPR) studies at X-band (~ 9.5 GHz) and Q-band (~ 34.5 GHz) of powder and single-crystal samples of the dinuclear compounds Cu2(TzTs)4, C40H36Cu2N8O8S8, and [Cu(flu)2DMF]2, C62H50Cu2F12N6O10. Meticulous investigations of their EPR data allow determining the antiferromagnetic interaction parameter, J0, between Cu(II) ions in the dinuclear unit (Hex = J0 S1·S2) as well as the principal values of both matrices g and D, where the first one is related to the Zeeman interaction [Hz = BB0(g1·S1 + g2·S2)] and the latter is associated with the anisotropic spin-spin interactions (Hani = S1·D·S2) between Cu(II) ion pairs in a dinuclear unit. In addition, EPR measurements of single-crystal samples of the compound Cu2(TzTs)4 allow detecting and estimating very weak exchange couplings between neighbour dinuclear units with an estimated magnitude |J\'| = (0.060 ± 0.015) cm-1: this coupling with the environment leads to decoherence (i.e. a quantum phase transition that collapses the dipolar interaction when the isotropic exchange coupling with neighbor dinuclear units equals the magnitude of the intradinuclear dipolar coupling). With reference to [Cu(flu)2DMF]2 compound, it was possible to simulate precisely the seven-line copper hyperfine splitting arising from n = 2 nonequivalent nuclei related to paramagnetic Cu2+ (I = 3/2) centers and, as a consequence of these accurate simulations, the principal values of the hyperfine interaction matrix A (Hhyper = S1·A·I1 + S2·A·I2) could be reliably obtained.
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Fratini, Simone. « Cristallisation des polarons à basse densité et transition isolant-métal : effets des interactions coulombiennes à longue portée ». Université Joseph Fourier (Grenoble), 1999. http://www.theses.fr/1999GRE10057.
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Cette these est consacree a l'etude de la transition isolant-metal dans les systemes polaires dopes. Les premiers chapitres constituent une breve introduction a la physique des polarons. Apres avoir passe en revue les differents modeles et approximations disponibles pour decrire la formation de polarons, nous nous concentrons sur le modele de frohlich, qui permet de traiter sur le meme pied la formation des polarons et les interactions coulombiennes a longue portee. Nous observons que la repulsion entre les particules est dominante dans un systeme de n polarons larges a basse densite, ce qui provoque leur cristallisation. Le troisieme chapitre est consacre a l'etude du cristal de polarons dans l'approximation de champ moyen de wigner. Les proprietes de l'etat fondamental sont analysees en fonction du couplage electron-phonon, de la densite et de la temperature, a travers la methode des integrales de chemin de feynman. En nous basant sur le critere de lindemann, nous montrons qu'il existe deux mecanismes en competition pour la transition isolant-metal : la fusion du cristal conduite par les fluctuations des particules localisees, relevante en couplage faible et intermediaire, et la dissociation des polarons, valable en couplage fort lorsque la polarisation est trop lente pour suivre le mouvement rapide des electrons. Le dernier chapitre concerne l'inclusion des interactions dipolaires entre les particules localisees. Nous developpons un modele quadratique, base sur l'approche de feynman, qui permet de decrire en premiere approximation le spectre d'excitations de basse energie et les proprietes dielectriques du cristal. La stabilite de la phase cristallisee par rapport aux excitations collectives est egalement analysee et nous proposons une signature experimentale pour la transition isolant-metal.
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Mahmoud, Salman. « Étude théorique des molécules diatomiques BN, SiN et LaH, structure électronique et spectroscopie ». Thesis, Montpellier 2, 2014. http://www.theses.fr/2014MON20080/document.
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Une étude théorique ab initio des structures électroniques des molécules Diatomiques polaires BN, SiN et LaH dans la représentation 2s+1Λ(+/-)Ont été effectués par la méthode du champ auto-cohérent de l'espace Actif complet (CASSCF), suivie par l'interaction de la configuration multiréférence (MRSDCI). La correction de Davidson, notée (MRSDCI+ Q), a ensuite été appliquée pour rendre compte de clusters ou agrégats quadruples non liés. L'ensemble de l'espace de configuration de CASSCF a été utilisé comme référence dans le calcul MRCI, qui a été effectués en utilisant le programme de calcul de chimie physique MOLPRO et en tirant parti de l'interface graphique Gabedit. Quarante-deux de plus bas états électroniques dans la représentation 2s+1Λ(+/-)au-dessous de 95000 cm-1 ont été étudiés de la molécule BN. Alors que vingt-huit états électroniques dans les représentations 2s+1Λ(+/-) jusqu'à 70000 cm-1 de la molécule de SiN ont été étudiés. D'autre part, les vingt-quatre bas états électroniques de LaH dans les représentations 2s+1Λ(+/-) au-dessous de 70000 cm-1 ont été étudiées par deux méthodes différentes et en prenant en considération l'effet des spin-orbite de la molécule LaH et nous avons observé la division énergétique des huit états électroniques. Les courbes d'énergie potentielle ont été construites avec la fréquence co-harmonique ωe, la distance internucléaire de l'équilibre re, les constantes de rotation Be. L'énergie électronique par rapport à l'état fondamentale Te a été calculé pour les états électroniques considérés comme des BN, SiN et la molécule LaH respectivement. En utilisant l'approche des fonctions canoniques, les valeurs propres Ev, les constantes rotationnelles Bv, la constante de distorsion centrifuge Dv et les abscisses des points de retournement Rmin and Rmax ont été calculés pour les états électroniques au niveau de vibration v=51 pour LaH molécule. Dix-huit et neuf états électroniques ont été étudiées pour la molécule BN et SiN respectivement. Pour LaH, vingt-trois états électroniques de la molécule LaH et l'effet de spin-orbite de molécule LaH sont donnés ici pour la première fois. La comparaison avec les données expérimentales et théoriques pour la plupart des constantes calculées démontre une très bonne précision. Enfin, ces résultats devraient ainsi mener à des études expérimentales plus poussées pour ces molécules. Nos résultats ont été publiés dans le Canadian Journal of Chemistry, Journal of Quantitative Spectroscopy and Radiative Transfer, nous avons deux autres articles en préparation à soumettreIn the present work a theoretical investigation of the lowest molecular states of BN, SiN and LaH molecule, in the representation 2s+1Λ(+/-), has been performed via complete active space self-consistent field method (CASSCF) followed by multireference single and double configuration interaction method (MRSDCI). The Davidson correction noted as (MRSDCI+Q) was then invoked in order to account for unlinked quadruple clusters. The entire CASSCF configuration space was used as a reference in the MRCI calculation which has been performed via the computational chemistry program MOLPRO and by taking advantage of the graphical user interface Gabedit. Forty-two singlet, triplet, and quintet lowest electronic states in the 2s+1Λ(+/-) representation below 95000 cm-1 have been investigated of the molecule BN. While twenty-eight electronic states in the representation2s+1Λ(+/-)up to 70000 cm-1 of the SiN molecule have been investigated.On the other hand the Twenty four low-lying electronic states of LaH in the representation 2s+1Λ(+/-) below 35000 cm-1 have been studied by two different methods and by taking into consideration the spin orbit effect of the molecule LaH we give in the energy splitting of the eight electronic states. The potential energy curves (PECs) together with the harmonic frequency ωe, the equilibrium internuclear distance re, the rotational constants Be and the electronic energy with respect to the ground state Te have been calculated for the considered electronic states of BN, SiN and LaH molecule respectively. Using the canonical functions approach, the eigenvalues Ev, the rotational constants Bv ,the centrifugal distortion constants Dv and the abscissas of the turning points Rmin and Rmax have been calculated for electronic states up to the vibrational level v =51 for LaH molecule.Eighteen and Nine electronic states have been investigated here for the first time for the molecules of BN and SiN respectively, while for LaH, news results are performed for twenty three electronic states of LaH molecule and the spin-orbit effect of LaH molecule is given here for the first time. A comparison with experimental and theoretical data for most of the calculated constants demonstrated a very good accuracy. Finally, we expect that the results of our work should invoke further experimental investigations for these molecules. Our results have been published in Canadian journal of chemistry, Journal of Quantitative Spectroscopy and Radiative Transfer and we have two other papers in preparation to submit
Livres sur le sujet "Electric dipolar interactions"
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Glazov, M. M. Hyperfine Interaction of Electron and Nuclear Spins. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198807308.003.0004.
Texte intégralRésumé :
This chapter discusses the key interaction–hyperfine coupling–which underlies most of phenomena in the field of electron and nuclear spin dynamics. This interaction originates from magnetic interaction between the nuclear and electron spins. For conduction band electrons in III–V or II–VI semiconductors, it is reduced to a Fermi contact interaction whose strength is proportional to the probability of finding an electron at the nucleus. A more complex situation is realized for valence band holes where hole Bloch functions vanish at the nuclei. Here the hyperfine interaction is of the dipole–dipole type. The modification of the hyperfine coupling Hamiltonian in nanosystems is also analyzed. The chapter contains also an overview of experimental data aimed at determination of the hyperfine interaction parameters in semiconductors and semiconductor nanostructures.
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Wolf, E. L. More about the Atmosphere, Molecules, and their Interaction with Radiation. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198769804.003.0007.
Texte intégralRésumé :
Electric dipole radiation is possible from certain molecules (but not with diatomics like oxygen and nitrogen) to make them active in intercepting and re-radiating electromagnetic waves in the atmosphere. Molecules of the greenhouse gas variety include carbon dioxide, ozone and water, as discussed in this chapter. Molecular contributions to the greenhouse heat-trapping effect are described, including sophisticated satellite measurements. The role of molecular absorption in altering the ground-level solar spectrum absorbed by solar farms is summarized. In this chapter we provide a molecular basis for the absorption and emission from the atmosphere, first discussed in Chapter 3. This gives a better understanding of the solar spectrum as seen on Earth, that feeds photovoltaic devices as well as heating the Earth’s surface, that in turn creates winds and waves that can be harvested.
Chapitres de livres sur le sujet "Electric dipolar interactions"
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Shtykov, Vitaliy V., et Sergey M. Smolskiy. « Interaction of Electric Dipoles ». Dans Introduction to Quantum Electronics and Nonlinear Optics, 55–92. Cham : Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-37614-7_2.
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Likhtenshtein, Gertz. « Spin Electron Dipolar and Contact Interactions ». Dans Electron Spin Interactions in Chemistry and Biology, 51–71. Cham : Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-33927-6_3.
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Avishai, Y., et M. Fabre de la Ripelle. « Electric Dipole Moment of 3He ». Dans Weak and Electromagnetic Interactions in Nuclei, 630–32. Berlin, Heidelberg : Springer Berlin Heidelberg, 1986. http://dx.doi.org/10.1007/978-3-642-71689-8_118.
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Ramsey, N. F. « Search for a Neutron Electric Dipole Moment ». Dans Weak and Electromagnetic Interactions in Nuclei, 861–65. Berlin, Heidelberg : Springer Berlin Heidelberg, 1986. http://dx.doi.org/10.1007/978-3-642-71689-8_171.
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Blanchard, John W., Alexander O. Sushkov et Arne Wickenbrock. « Magnetic Resonance Searches ». Dans The Search for Ultralight Bosonic Dark Matter, 173–200. Cham : Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-95852-7_6.
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AbstractUltralight bosonic dark matter (UBDM), such as axions and axionlike particles (ALPs), can interact with Standard Model particles via a variety of portals. One type of portal induces electric dipole moments (EDMs) of nuclei and electrons and another type generates torques on nuclear and electronic spins. Several experiments search for interactions of spins with the galactic dark matter background via these portals, comprising a new class of dark matter haloscopes based on magnetic resonance.
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Lobashev, V. M. « An Experimental Search for the Neutron Electric Dipole Moment ». Dans Weak and Electromagnetic Interactions in Nuclei, 866–70. Berlin, Heidelberg : Springer Berlin Heidelberg, 1986. http://dx.doi.org/10.1007/978-3-642-71689-8_172.
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Morsch, H. P., B. Bochev, T. Kutsarova, R. M. Lieder, W. Gast, G. Hebbinghaus, A. Krämer-Flecken, W. Urban et J. P. Didelez. « Cooling of Hot Rotating Nuclei by Electric and Magnetic Dipole Radiation ». Dans Weak and Electromagnetic Interactions in Nuclei, 111–15. Berlin, Heidelberg : Springer Berlin Heidelberg, 1986. http://dx.doi.org/10.1007/978-3-642-71689-8_27.
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Bertrand, Patrick. « Effects of Dipolar and Exchange Interactions on the EPR Spectrum. Biradicals and Polynuclear Complexes ». Dans Electron Paramagnetic Resonance Spectroscopy, 241–87. Cham : Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-39663-3_7.
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von Brentano, P., A. Zilges, N. V. Zamfir et R. D. Herzberg. « Low Lying Electric Dipole Excitations and the Interacting Boson Model ». Dans Symmetries in Science VII, 123–31. Boston, MA : Springer US, 1994. http://dx.doi.org/10.1007/978-1-4615-2956-9_12.
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Bohle, D., Th Guhr, U. Hartmann, K. D. Hummel, G. Kilgus, U. Milkau et A. Richter. « Properties of a New Magnetic Dipole Mode Discovered in Low Energy Electron Scattering ». Dans Weak and Electromagnetic Interactions in Nuclei, 311–20. Berlin, Heidelberg : Springer Berlin Heidelberg, 1986. http://dx.doi.org/10.1007/978-3-642-71689-8_66.
Texte intégralActes de conférences sur le sujet "Electric dipolar interactions"
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Zhang, Jiaming, Ken Morita, Verdad C. Agulto, Kosaku Kato et Makoto Nakajima. « Electron Dynamics of Ultrafast Vector Vortex Laser Irradiation ». Dans JSAP-Optica Joint Symposia, 19p_C43_6. Washington, D.C. : Optica Publishing Group, 2024. https://doi.org/10.1364/jsapo.2024.19p_c43_6.
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The dynamical effects of lasers have garnered widespread attention, holding significant research value in fields such as optical tweezers (optical trapping), laser processing, and photonic nanojets [1,2]. Studies related to optical dynamical effects primarily focus on dielectric materials [3,4]. On the other hand, research on interactions between optical light and single-charged electrons is mainly focused on the conduction electron excitations in the semiconductors involving the quantum transitions, leaving their dynamics insufficiently explored. Recently, we reported an experiment using ultrafast lasers to observe electron relativistic effects [5], demonstrating the enormous potential of optoelectronic interactions. Studying the dynamic effects of lasers on electrons in free carriers in simple materials rather than in dielectric materials, which are assemblies of dipoles, provides a deeper understanding of the dynamics of lasers and the photon-electron interactions.
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Wang, Ming-Wen. « Alignment of MWCNTs in Polymer Composites by Dielectrophoresis ». Dans ASME 2008 First International Conference on Micro/Nanoscale Heat Transfer. ASMEDC, 2008. http://dx.doi.org/10.1115/mnht2008-52160.
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Successful structural reinforcement of polymer matrices by carbon nanotube has been shown where significant improvement of mechanical properties was achieved at very low carbon nanotube loading. Due to the mechanical properties of aligned composites is better than random has been demonstrated; the conception is not easy to perform in carbon nanotube polymer composites via conventional techniques. Here, we report a novel operation to actively align and network multi-wall carbon nanotubes (MWCNTs) in a polymer matrix. In this process, MWCNTs were aligned via AC electric field induced dipolar interactions among the nanotubes in a viscous matrix followed by immobilization by curing polymerization under continued application of the anisotropic electric field. In situ SEM verified the electrostatic stabilization of the MWCNTs in the dispersion and the orientation and agglomeration caused by the dielectrophoretic force. Alignment of MWCNTs was controlled as a function of magnitude, frequency, and application time of the applied dielectrophoresis. In the present work, MWCNTs are not only aligned along the field, but also migrate laterally to form thick. The actively aligned MWCNTs amplify the flexural modulus and wear-resisting property.
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Zyss, Joseph, Ifor Samuel, Céline FIORINI, Fabrice Charra et Jean-Michel Nunzi. « Permanent All Optical Poling of An Octupolar Dye ». Dans Organic Thin Films for Photonic Applications. Washington, D.C. : Optica Publishing Group, 1995. http://dx.doi.org/10.1364/otfa.1995.tue.1.
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The predominant class of molecular systems considered so-far towards applications in the realm of quadratic nonlinear optics has been derived from the all-pervading "molecular diode" template as exemplified by paranitroaniline-like molecules. The underlying basic paradigm consists in the dipolar anchoring of an interacting couple of electron donor and acceptor groups to a conjugated π electron linkage(1). The virtue of such a configuration is to provide a significant electronic charge displacement in the ground state which is further enhanced upon directional optical excitation towards the charge-transfer level. This basic mechanism has been confirmed by nearly two decades of experiments in solutions, crystals and polymer media with the two-level quantum model providing solid theoretical support(2). Both the Electric Field Induced Second Harmonic (EFISH) experiment and the current poled polymer technology essentially depend on the existence and magnitude of a strong ground state dipole μ contributing to the μ.E coupling potential between individual molecules and the externally applied de poling field E.
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Erol, Anil, Saad Ahmed, Paris von Lockette et Zoubeida Ounaies. « Analysis of Microstructure-Based Network Models for the Nonlinear Electrostriction Modeling of Electro-Active Polymers ». Dans ASME 2017 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/smasis2017-3979.
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Relaxor ferroelectric polymers are a unique branch of electro-active polymers (EAPs) that generate high electromechanical strain with relatively low hysteresis and high nonlinearity. Polyvinylidene fluoride-based EAPs possess these qualities due to the semicrystalline nature of their microstructure. The interactions of electric dipoles within the microstructure of the material generate large strains under an external electric field, and the reduced crystalline domain sizes yield a relaxor effect by exhibiting low hysteresis and hyperelastic properties. This phenomenon has been partially modeled by previous works, but micro-electro-mechanisms for electrostriction in the microstructure have been largely ignored. This study focuses on the effects of various microstructural frameworks on the nonlinear dielectric behavior of dipole-based, semicrystalline EAPs. The Helmholtz free energy function of a microscopic representative volume element (RVE) is composed of an electrostatic energy and an elastic energy. The dipole-dipole interaction energy is prescribed for the electrostatic forces observed among the crystalline regions, and the elastic component attributed to the relaxation of the amorphous phase is modeled by the hyperelastic eight-chain model, which is microstructure-based. The RVE of the system is modeled by a central dipole surrounded by dipoles whose relative spatial locations are determined by a probability distribution function (PDF). The hyperelastic amorphous phase constitutes the volume separating the central and surrounding dipoles. The free energy of the RVE is implemented into a continuum description of the equilibrium of the system to obtain electromechanical relations. Additionally, this electromechanical response data is applied to a 1D structural mechanics model for simulating the large deformation of a multi-layered beam. The effects of microstructure on electrostrictive coupling are explored by varying the centers and deviations of dipole locations within the PDF. Discrete microstructural arrangements representing 3-chain network averaging schemes may be studied alongside more continuous ellipsoidal or random models of dipole spatial arrangements. The simulation results of the PDF-based networks are in good agreement with experimental data. The results indicate that the electrostrictive behavior of EAPs is strongly dependent on (1) the relative dipole spatial locations and (2) the extent of the regions containing dipoles, which represent crystalline domains. The model finds that adding extra crystalline domains in the network averaging schemes generates a better characteristic behavior due to a broader averaging of spatial orientations. These results offer a gateway to predicting microstructurally-dependent dipole-based behavior that can lead to the predictive theoretical tailoring of microstructures for desired electromechanical properties.
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Bandrauk, André D., et O. F. Kalman. « Dynamics in Intense Fields - Beyond the Dipole Approximation ». Dans Multiple Excitations of Atoms. Washington, D.C. : Optica Publishing Group, 1986. http://dx.doi.org/10.1364/mea.1986.tuc1.
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We have recently shown in a series of papers [1-7] that coupled equations methods of quantum collision theory can be conveniently used to investigate processes such as direct photodissociation [1-2], Resonance Raman Scattering in weak and strong fields [3-5], and higher order nonlinear spectroscopies [6-7] for diatomics involving several well isolated excited electronic states. This was done using the dressed molecule picture [8-12] of molecule-radiation interaction, wherein photon states are explicitly included into the theoretical description. All these methods are adequate only in the case of well isolated electronic states. There is an urgent need to derive a priori the most efficient representation for general electron-nuclear-radiation field systems such as occurs in strong field laser chemistry. In recent work we have examined this problem in an effort to incorporate as much as possible the electromagnetic field into the dynamics [13-14]. One might surmise that classical approaches should work sufficiently well at the high field intensities described here, and much work has been pursued in that direction. As we have pointed out previously, this involves treating both the molecule and the field classically. For electron-radiation interactions one would prefer a quantum formulation, since electronic states are, as a result of their large excitation energies, true quantum states. Furthermore, quantum mechanics leads to a linear theory of interactions whereas classical mechanics is a highly nonlinear theory [15]. Thus using a quantum formulation of matter- field interactions [16-17], we have been able to exploit methods of early (non-covariant) quantum electrodynamics (QED). In particular we have shown that the Bloch-Nordsieck (BN) representation [18-20] (which leads naturally to the concept of coherent states in momentum space was very convenient as a method of introducing strong field effects directly into the quantum dynamics of molecular systems. Coulomb gauge ( A → . p → ) and Electric Field Gauge ( E → . r → ) representations were shown to be poor zeroth order approximations for the dressed molecular eigenstates in the presence of strong fields, i.e., the adiabatic coupled equations for the latter two gauges define the appropriate adiabatic state as unperturbed (zero field) molecular states [13-14].
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Fiorini, Céline, Fabrice Charra, Jean-Michel Nunzi et Joseph Zyss. « Permanent all-optical poling of octupolar molecules ». Dans The European Conference on Lasers and Electro-Optics. Washington, D.C. : Optica Publishing Group, 1994. http://dx.doi.org/10.1364/cleo_europe.1994.cmk2.
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Conjugated intramolecular charge transfer systems such as the paranitroaniline derivatives have remained so far one of the most studied classes of organic molecules with enhanced quadratic optical properties. Nevertheless, under the influence of dipole/dipole interactions such molecules are prone to form light scattering aggregates in dilute media or crystallize in centrosymmetric lattices, that results thus in the material having no macroscopic second-order susceptibility. This approach was recently revised, and a new engineering scheme was proposed: octupolar molecules, that can possess large nonlinear optical properties together with good transparency but that do not possess a permanent dipole moment, may circumvent the problem discussed above.1,2 However, since the absence of dipole moment in such molecules prevents dipolar orientation, no polar order can be expected from standard polarization techniques such as Corona poling.
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Silverman, M. P. « Nonclassical rotational optical activity in atomic hydrogen ». Dans OSA Annual Meeting. Washington, D.C. : Optica Publishing Group, 1991. http://dx.doi.org/10.1364/oam.1991.we4.
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As a result of the coupling between the spin of the earth and the spin angular momentum of the electron and proton, terrestrial atomic hydrogen should exhibit a nonforbidden circular birefringence and consequent optical rotary power for microwave radiation near the 1S1/2(f= 1) - S1/2(f = 0) hyperfine splitting frequency of 1420 MHz. Rotation of the earth splits the degenerate 1S(f= 1) magnetic substates, thereby giving rise, through a magnetic dipole interaction with circularly polarized microwaves, to chirally asymmetric magnetic permeabilities. The predicted circular birefringence can be some 10 orders of magnitude larger than that previously attributable to chirally asymmetric electric permittivities deriving from virtual electric dipole transitions between electronic manifolds induced by incident radiation falling in the visible and UV portions of the spectrum.1
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Jen, Alex K.-Y., et Ching-Fong Hsu. « Recent Progress of Electro-optic Polymers for Device Applications ». Dans Solid State Lasers : Materials and Applications. Washington, D.C. : Optica Publishing Group, 1997. http://dx.doi.org/10.1364/sslma.1997.tha2.
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Electro-optic (E-O) polymers have drawn great interests in recent years because of their potential applications in photonics devices such as electro-optic modulators and switches, optical data storage and information processing1-2. Recent interests have been focused on the design and development of polymeric material systems (active and passive) with large E-O coefficients and high thermal, temporal, chemical and phtochemical stability3-8. The E-O response of a active polymer commonly arises from the electric field induced alignment of its second-order nonlinear optical (NLO) chromophore, either doped as a guest/host system or covalently bonded as a side-chain. Because of the strong interaction among the electric dipoles, the poled structure is in a meta-stable state; the poled NLO chromophores which possess large dipole moment will tend to relax back to the randomly oriented state. As a result, the stability of the poled structure strongly depends on the rigidity of the overall material system. This paper provides a brief review of the latest developments of highly efficient and thermally stable chromophores and polymers for device applications.
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Oliva-Avilés, A. I., F. Avilés et V. V. Zozulya. « Modeling the Electric Field-Guided Motion of Interacting Carbon Nanotubes Using a Dielectrophoretic Framework ». Dans ASME 2015 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/smasis2015-8911.
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A theoretical investigation of the dynamic response of a pair of interacting carbon nanotubes (CNTs) dispersed in a liquid medium under the presence of an alternating current (AC) electric field is presented. The proposed modeling strategy is based on the dielectrophoretic (DEP) theory and classical electrodynamics, and considers the effect of an applied AC electric field on the rotational and translation motion of interacting CNTs represented as electrical dipoles. The mutual interaction between a pair of adjacent CNTs stems from the presence of DEP-induced charges on the CNTs and, as such, contributes to the rotational and translational dynamics of the system. Based on experimental evidence, the parameters which are expected to cause a major contribution to the CNTs motion are investigated for different initial configurations. Based on the obtained results, it is here predicted that high electric field frequencies, long CNTs, high values of electrical permittivity and conductivity of CNTs immersed in solvents of high polarity promote faster rotational and translational motion and therefore faster equilibrium conditions (CNT tip-to-tip contact and horizontal alignment). The results incorporate important knowledge towards a better understanding of the complex mechanisms involved in the efforts of tailoring CNT networks by electric fields.
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Nayak, Sudhanshu Kumar, Md Soif Ahmed, Chinmay Barman, Rahul Murali, Bota Bhavani, Seelam Prasanthkumar, Lingamallu Giribabu et Sai Santosh Kumar Raavi. « Nonlinear Coherent Light-matter Interaction : Promising all-Optical Switching, Logic Gate and Optical Limiting Applications ». Dans JSAP-Optica Joint Symposia. Washington, D.C. : Optica Publishing Group, 2023. http://dx.doi.org/10.1364/jsapo.2023.21a_p01_6.
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Spatial self-phase modulation (SSPM) is a nonlinear optical (NLO) coherent interaction between light and matters. The phase gets self-modulated due to the change of nonlinear refractive index through the nonlinear Kerr effect and produce diffraction rings at the far fields. [1] Porphyrins are the organic molecules with π-conjugation electron rich systems, they possess delocalized electric field distribution and large dipole moments that lead to have significant electrical polarization, which is a profit for higher NLO response. These molecules have various application in photovoltaics, photonics, optoelectronics, etc. [2, 3] Herein, we report the NLO properties of four metalated porphyrin-napthalimide based donor-acceptor systems named as PN-Zn, PN-Ni, PN-Cu, and PN-Fb using SSPM and continuous wave (CW) Z-scan method for exploring various optoelectronic applications like optical limiting, optical switching, and logic gates, etc.
Rapports d'organisations sur le sujet "Electric dipolar interactions"
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Haxton, W. C. Limits on CP nonconserving interactions from electric dipole moments. Office of Scientific and Technical Information (OSTI), septembre 1994. http://dx.doi.org/10.2172/10181241.
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Haxton, W. C., A. Hoering et M. J. Musolf. Constraints on T-odd and P-even hadronic interactions from nucleon, nuclear, and atomic electric dipole moments. Office of Scientific and Technical Information (OSTI), juin 1994. http://dx.doi.org/10.2172/10156361.
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