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Polarization holography for vortex retarders recording: laboratory demonstration
http://hdl.handle.net/2268/182068
Titre: Polarization holography for vortex retarders recording: laboratory demonstration
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<br/>Auteur, co-auteur: Piron, Pierre; Blain, Pascal; Décultot, Marc; Mawet, Dimitri; Habraken, Serge
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<br/>Résumé: This paper will present a prototype of the first set of vortex retarders made of liquid crystal polymers recorded by
polarization holography. Vortex retarders are birefringent plates characterized by a rotation of their fast axis.
Liquid crystals possess birefringent properties and they are locally orientable. Their orientation is defined by
the perpendicular to the local orientation of the recording field. Polarization holography is a purely optical recording
method. It is based on the superimposition of coherent and differently polarized beams. It is used to shape
the electric field pattern to enable the recording of vortex retarders. The paper details the mathematical model of
the superimposition process. The recording setup is exposed; it is characterized by a nearly common path interferometer.
Two sets of measurements allowing the prediction of the retarder’s features are presented and compared.
Finally, the experimentally recorded retarder is shown, its characteristics are investigated and compared to
the predicted ones.Investigation of intravalence, core-valence and core-core electron correlation effects in polonium atomic structure calculations
http://hdl.handle.net/2268/182067
Titre: Investigation of intravalence, core-valence and core-core electron correlation effects in polonium atomic structure calculations
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<br/>Auteur, co-auteur: Quinet, PascalImportance of wavenumber dependence of Biot numbers in one-sided models of evaporative Marangoni instability: horizontal layer and spherical droplet
http://hdl.handle.net/2268/181868
Titre: Importance of wavenumber dependence of Biot numbers in one-sided models of evaporative Marangoni instability: horizontal layer and spherical droplet
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<br/>Auteur, co-auteur: Machrafi, Hatim; Rednikov, Alexey; Colinet, Pierre; Dauby, PierreNumerical modeling of the cardiac mechano-electric feedback within a thermo-electro-mechanical framework. Study of its consequences on arrhythmogenesis.
http://hdl.handle.net/2268/181760
Titre: Numerical modeling of the cardiac mechano-electric feedback within a thermo-electro-mechanical framework. Study of its consequences on arrhythmogenesis.
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<br/>Auteur, co-auteur: Collet, Arnaud
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<br/>Résumé: This doctoral study characterizes, for simple geometries, the cardiac autonomous electrical activity induced by the mechanical deformations of the myocardium via the mechano-electric feedback within a thermo-electro-mechanical framework. The underlying fundamental mechanisms are highlighted and discussed in detail.
In a healthy heart, the mechano-electric feedback acts as a regulator able to damp mechanical perturbations undergone by the heart, by appropriately modulating electrical activity shortly after these perturbations. In this way, a new healthy electromechanical situation is recovered. However, under certain conditions, this feedback can be a generator of dramatic cardiac arrhythmias by inducing local electrical depolarizations resulting from abnormal cardiac muscle tissue deformations. These local perturbations can then propagate in the whole heart and, thus, lead to global cardiac dysfunctions.
The one- and two-dimensional models developed in this work to study the arrhythmogenic consequences of the mechano-electric feedback within a thermo-electro-mechanical framework account for three couplings: the excitation-contraction coupling, the mechano-electric feedback, and the thermo-electric coupling. The excitation-contraction coupling allows the mechanical contraction of cardiac muscle cells resulting from the electrical excitation of these cells, triggered by a propagating action potential initially generated by the sino-atrial node in a healthy heart. The mechano-electric feedback takes into account the influence of mechanical deformations on the electrical activity, both at the cell and the macroscopic level. The thermo-electric coupling then modulates certain electrical properties due to a temperature change.
The excitation-contraction coupling is modeled in a phenomenological way by combining the Aliev-Panfilov model and the Rogers-McCulloch model. The propagation of the electrical excitation through cardiac muscle tissue is modeled by using the monodomain approach. The mechano-electric feedback is taken into account by considering two different contributions, namely the physiological contribution (physiological feedback) and the geometric contribution (geometric feedback). The physiological feedback consists in the onset of stretch-activated currents due to the deformations of the cardiac muscle tissue via specific mechanosensitive channels. Regarding the geometric feedback, it simply reflects that the propagation of the depolarization waves is altered by the deformations of the geometry. The thermo-electric coupling is modeled via a dependence with respect to the temperature which is exponential for the gating kinetics of ion channels, exponential for the kinetics of the active tension development in cardiomyocytes, and linear for the ionic conductances.
This study shows that the mechano-electric feedback can be arrhythmogenic under specific conditions. In particular, this work clearly reveals that the size of the domain and the importance of stretch-activated currents are key factors in the behavior of the autonomous electrical activity induced by the mechano-electric feedback. This doctoral study also shows that temperature variations such as those undergone by the heart during therapeutic hypothermia or hyperthermia play a central role in the cardiac electromechanical behavior. Moreover, this work emphasizes the influence of the initial conditions on the electromechanical behavior of cardiac tissue. In the one-dimensional framework, an important result of this work is that the disappearance of the autonomous electrical activity induced by the deformations of the cardiac muscle can be associated with different types of bifurcation phenomena, depending on the values of the parameters. These bifurcations, which correspond in fact to different ways for the AEA to vanish, are emphasized and discussed in detail.; Cette étude doctorale caractérise, dans le cadre de géométries simples, l'activité électrique autonome cardiaque induite par les déformations mécaniques du myocarde au travers du feedback mécano-électrique dans un contexte thermo-électro-mécanique. Les mécanismes fondamentaux sous-jacents sont mis en évidence et discutés en détails.
Dans un coeur sain, le feedback mécano-électrique agit comme un régulateur capable d'amortir des perturbations mécaniques ressenties par le coeur, en modulant de manière appropriée l'activité électrique subséquente à ces perturbations. De cette façon, une nouvelle situation électromécanique saine est retrouvée. En revanche, dans certaines conditions particulières, ce feedback peut être à l'origine d'arythmies cardiaques importantes en induisant localement des dépolarisations électriques générées par des déformations anormales du tissu musculaire cardiaque. Ces perturbations locales peuvent alors se propager à l'ensemble du tissu et de ce fait, induire des dysfonctionnements cardiaques globaux.
Les modèles unidimensionnels et bidimensionnel développés dans ce travail afin d'étudier les conséquences arythmogènes du feedback mécano-électrique dans un cadre thermo-électro-mécanique prennent en compte trois couplages : le couplage excitation-contraction, le feedback mécano-électrique et le couplage thermo-électrique. Le couplage excitation-contraction permet la contraction mécanique des cellules musculaires cardiaques qui résulte de l'excitation électrique de ces dernières provoquée par le passage d'un potentiel d'action, initialement généré au sein du noeud sinusal dans un coeur sain. Le feedback mécano-électrique rend compte de l'influence des déformations mécaniques sur l'activité électrique tant au niveau cellulaire qu'au niveau macroscopique. Enfin, le couplage thermo-électrique module certaines propriétés électriques suite à un changement de température.
Le couplage excitation-contraction est modélisé de manière phénoménologique en combinant les modèles de Aliev-Panfilov et de Rogers-McCulloch. La propagation de l'excitation électrique au sein du tissu musculaire cardiaque est modélisée en utilisant l'approche monodomaine. Le feedback mécano-électrique est pris en compte en considérant deux contributions distinctes, à savoir la contribution physiologique (feedback physiologique) et la contribution géométrique (feedback géométrique). Le feedback physiologique consiste en l'apparition de courants induits par les déformations du tissu musculaire cardiaque au travers de canaux mécano-sensibles particuliers. Quant au feedback géométrique, il traduit simplement que la propagation des ondes de dépolarisation est altérée par les déformations de la géométrie qui les supporte. Le couplage thermo-électrique est modélisé via une dépendance vis-à-vis de la température qui est exponentielle pour la cinétique d'ouverture et de fermeture des canaux ioniques, exponentielle pour la cinétique relative au développement de la tension active au sein des cardiomyocytes et linéaire pour les conductances ioniques.
Cette étude montre que le feedback mécano-électrique peut dans certaines conditions particulières être arythmogène. En particulier, cette étude montre clairement que la taille du domaine ainsi que la présence plus ou moins importante des courants induits par les déformations sont des facteurs déterminants dans le comportement de l'activité électrique autonome induite par le feedback mécano-électrique. Ce travail montre aussi que des variations de température telles que celles subies par le coeur lors d'une hypothermie thérapeutique ou lors d'une hyperthermie jouent un rôle central sur le comportement électromécanique cardiaque. Par ailleurs, cette étude met également en évidence l'importance des conditions initiales d'excitation sur le comportement électromécanique du tissu musculaire cardiaque. Dans le contexte unidimensionnel, un résultat important de ce travail est que la disparition de l'activité électrique autonome induite par les déformations du muscle cardiaque peut être associée à différents types de phénomènes de bifurcation qui dépendent des valeurs des paramètres. Ces bifurcations, correspondant en fait à différents chemins que l'activité électrique autonome emprunte pour disparaître, sont mises en évidence et discutées en profondeur.Thermal conductivity: application to magnetic rare-earth compounds
http://hdl.handle.net/2268/181691
Titre: Thermal conductivity: application to magnetic rare-earth compounds
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<br/>Auteur, co-auteur: Rassili, AhmedRelation between convective thermal patterns and heat flux through an evaporating surface via 2D and 3D numerical simulations
http://hdl.handle.net/2268/181683
Titre: Relation between convective thermal patterns and heat flux through an evaporating surface via 2D and 3D numerical simulations
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<br/>Auteur, co-auteur: Machrafi, Hatim; Iorio, Carlo; Dauby, PierreWhy are flux avalanches deflected by a metallic layer?
http://hdl.handle.net/2268/181598
Titre: Why are flux avalanches deflected by a metallic layer?
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<br/>Auteur, co-auteur: Brisbois, Jérémy
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<br/>Résumé: Sudden avalanches of magnetic flux bursting into a superconducting sample are deflected from their trajectories when they encounter a conductive layer deposited on top of the superconductor. Remarkably, in some cases the flux is totally excluded from the area covered by the conductive layer. Even if this phenomenon has been known for a few years, there is currently no theoretical model describing it. Moreover, the question whether the deflection would also be observed for a single vortex entering the region covered by a metallic layer is still unanswered.
In this work we use the magneto-optical imaging (MOI) technique, based on the Faraday effect, to show that a conductive layer (Cu) can repel flux avalanches triggered in an underlying superconducting film (Nb) (see figure). We present a simple classical model that accounts for the deflection of a single vortex and considers a magnetic monopole approaching a semi-infinite conductive plane. This model suggests the important role played in the avalanche deflection by electromagnetic braking, arising from the eddy currents induced by the moving vortex in the metal. Moreover, we have found a decrease of the vortex damping coefficient due to the metallic sheet at large vortex velocities, correcting early theoretical descriptions where a linear behaviour was proposed.Chaotic Bohmian trajectories for the hydrogen atom
http://hdl.handle.net/2268/181585
Titre: Chaotic Bohmian trajectories for the hydrogen atom
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<br/>Auteur, co-auteur: Cesa, Alexandre; Struyve, Ward; Martin, John
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<br/>Résumé: In Bohmian mechanics, a single-particle quantum system is described in part by its wave function and in part by the actual position of the particle. The trajectory of the latter can be computed using the guiding equation. This equation states that the velocity of the particle is proportional to the usual probability current associated with its wave function. In this work, we study the quantum trajectory of a single particle in a Coulomb potential whose eigenstates are the well known eigenstates of the hydrogen atom. More precisely, we focus on the relation between chaotic Bohmian trajectories and the motion of wave function nodes. At wave function nodes i.e., where the wave function vanishes, the velocity is not defined which generically induces vorticity. In order to probe chaos, we compute Poincaré map and we numerically evaluate Lyapounov exponents, which characterize the divergence of close trajectories as time increases. For the 2d Coulomb potential, although the superposition of two eigenstates with different energies can lead to an arbitrary high number of moving nodes of the wave function, the Bohmian trajectories display no trace of chaos. This absence of chaotic behaviour originates from the existence of a constant of motion. Therefore, the motion and the number of nodes do not constitute a sufficient condition for the emergence of chaos in Bohmian mechanics. For superpositions of more than two eigenstates, there is no constant of motion, there are moving nodes and we find that the Bohmian trajectories are chaotic.Leidenfrost drops: effect of gravity
http://hdl.handle.net/2268/181529
Titre: Leidenfrost drops: effect of gravity
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<br/>Auteur, co-auteur: Maquet, Laurent; Brandenbourger, Martin; Sobac, Benjamin; Biance, Anne-Laure; Colinet, Pierre; Dorbolo, StéphaneDetermination of the lower critical field Hc1(T) in FeSe single crystals by magnetization measurements
http://hdl.handle.net/2268/181225
Titre: Determination of the lower critical field Hc1(T) in FeSe single crystals by magnetization measurements
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<br/>Auteur, co-auteur: Abdel-Hafiez, M; Vasiliev, A.N.; Chareev, D.A.; Moshchalkov, V.V.; Silhanek, Alejandro
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<br/>Résumé: In a recent work, Abdel-Hafiez et al. we have determined the temperature dependence of the lower critical field Hc1(T) of a FeSe single crystal under static magnetic fields H parallel to the crystallographic c axis. The temperature dependence of the first vortex penetration field has been experimentally obtained by two independent methods and the corresponding Hc1(T) was deduced by taking into account demagnetization factors. In general, the first vortex penetration field may not reflect the true Hc1(T) due to the presence of surface barriers. In this work we show that magnetic hysteresis loops are very symmetric close to the critical temperature Tc = 9 K evidencing the absence of surface barriers and thus validating the previously reported determination of Hc1(T) and the main observations that the superconducting energy gap in FeSe is nodeless.Remote control of self-assembled magnetocapillary microswimmers
http://hdl.handle.net/2268/181159
Titre: Remote control of self-assembled magnetocapillary microswimmers
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<br/>Auteur, co-auteur: Grosjean, Galien; Lagubeau, Guillaume; Hubert, Maxime; Vandewalle, Nicolas
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<br/>Résumé: Physics governing the locomotion of microorganisms and other microsystems is dominated by viscous damping. An effective swimming strategy involves the non-reciprocal and periodic deformations of the considered body. Herein, we show that a magnetocapillary-driven self-assembly, composed of three soft-ferromagnetic beads, is able to swim along a liquid-air interface when driven by an external magnetic field. Moreover, the system can be fully controled, opening ways to explore low Reynolds number swimming and to create micromanipulators in various applications.Lattice dynamics in antimony and tellurium based phase-change materials
http://hdl.handle.net/2268/180957
Titre: Lattice dynamics in antimony and tellurium based phase-change materials
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<br/>Auteur, co-auteur: Simon, Ronnie ErnstPhotochemical generation of reactive oxygen species using plasmonic nanoparticles
http://hdl.handle.net/2268/180850
Titre: Photochemical generation of reactive oxygen species using plasmonic nanoparticles
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<br/>Auteur, co-auteur: Lismont, Marjorie
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<br/>Résumé: During his lecture entitled “ There is plenty of room at the bottom ”, Richard Feyn- man foresaw the possibility of manipulating material at the scale of individual atoms and molecules. Although Feynman’s conceptual idea of a nanoworld was evoked in 1959, the nanoscience and nanotechnology revolution began 30 years later with the ability to see at the atomic scale with the invention of electronic microscopy and related tools. The size range that has attracted so much attention over these last 30 years is typically from 100 nanometers down to the atomic level. Subsequently, nanomaterials were defined as materials, which have structured components with at least one dimension in this size range. For instance, material with three nanometric dimensions defines a nanoparticle.
Among the variety of core materials available to synthesize nanoparticles, noble metal nanoparticles, i.e. gold and silver, have fascinated people for centuries owing to their bright and intense colors, used in particular as decorative pigments in cathedral stained glasses and artworks. The red and yellow colors displayed by gold and silver nanoparti- cles arise from their interaction with light, which one induces collective oscillations of free electrons at the nanoparticle surface in resonance with the light field. This phenomenon is commonly known as the localized surface plasmon resonance. Their remarkable optical properties and the intense electric field generated by plasmonics nanoparticles have brought these nanomaterials in the forefront of nanotechnology research, ranging from photonics to medicine.
Shining light on plasmonic nanoparticles to push back limitations of light-activated therapy and so taking part to the societal challenge of cancer treatment improvement defines the global framework of the thesis. Falling within the nanomedicine topic, this one more precisely deals with the development of efficient plasmonic nano-drugs using light to cure diseases. Clearly, nanoplasmonics, which explores how electromagnetic field can be confined over dimension on the order or smaller than the wavelength of light, has come a long way since the stained glass of Roman times.Transport of Bose-Einstein Condensates through Aharonov-Bohm rings
http://hdl.handle.net/2268/180756
Titre: Transport of Bose-Einstein Condensates through Aharonov-Bohm rings
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<br/>Auteur, co-auteur: Chrétien, Renaud; Dujardin, Julien; Petitjean, Cyril; Schlagheck, Peter
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<br/>Résumé: We study the one-dimensional (1D) transport properties of an ultracold gas of Bose-Einstein condensed atoms through Aharonov-Bohm (AB) rings. Our system consists of a Bose-Einstein condensate (BEC) that is outcoupled from a magnetic trap into a 1D waveguide which is made of two semi-infinite leads that join a ring geometry exposed to a magnetic flux φ. We specifically investigate the effects of a small atom-atom contact interaction strength on the AB oscillations. The main numerical tools that we use for this purpose are a mean-field Gross-Pitaevskii (GP) description and the truncated Wigner (tW) method. The latter allows for the description of incoherent transport and corresponds to a classical sampling of the evolution of the quantum bosonic many-body state through effective GP trajectories. We find that resonant transmission peaks move with an increasing interaction strength and can be suppressed for sufficiently strong interaction. We also observe that the coherent transmission blockade due to destructive interference at the AB flux φ = π is very robust with respect to the interaction strength.Preliminary results for a hydrogen maser cavity in the TE111 mode
http://hdl.handle.net/2268/180731
Titre: Preliminary results for a hydrogen maser cavity in the TE111 mode
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<br/>Auteur, co-auteur: Van Der Beken, Emeline; Léonard, Daniel; Counet, Arnaud; Bastin, Thierry
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<br/>Résumé: An analysis of a hydrogen maser working with an unusual TE111 mode is presented. Different simulations have been carried out and are compared with preliminary results obtained for such a maser. In contrast to standard hydrogen maser that exploits the TE011 mode, the TE111 mode allows one to design hydrogen masers with significant reduced dimensions which represents a huge benefit for space applications and in particular for the global positioning system.Investigation of Demagnetization in HTS Stacked Tapes Implemented in Electric Machines as a Result of Crossed Magnetic Field
http://hdl.handle.net/2268/180535
Titre: Investigation of Demagnetization in HTS Stacked Tapes Implemented in Electric Machines as a Result of Crossed Magnetic Field
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<br/>Auteur, co-auteur: Baghdadi, M.; Ruiz, H. S.; Fagnard, Jean-François; Zhang, M.; Wang, W.; Coombs, T. A.
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<br/>Résumé: This paper investigates the practical effectiveness of employing superconducting stacked tapes to superconducting electric machinery. The use of superconducting bulks in various practical applications has been addressed extensively in the literature. However, in practice, dramatic decrease in magnetization would occur on superconducting bulks due to the crossed field effect. In our study, we employed the superconducting stacked tapes in a synchronous superconducting motor, which was designed and fabricated in our laboratory, aiming to lessen demagnetization due to crossed field effect in comparison with superconducting bulks. Applying the transverse AC field, the effects of frequency, amplitude, and number of cycles of the transverse magnetic field are discussed. Furthermore, a stack of 16 layers of superconducting tapes is modelled and the consequences of applying the crossed magnetic field on the sample are evaluated. The confrontation between experiments and simulation allows us to thoroughly understand the crossed field effects on stacked tapes. At the end, a preventive treatment, based on the shielding characteristic of superconductor and materials with high permeability, i.e. $mu$-metal and metalic glass, is suggested. On the other hand, the shielding feature of aforementioned materials will hinder the penetration of magnetic field and, consequently, reduction of the demagnetization will be attained.Measurements on magnetized GdBCO pellets subjected to small transverse ac magnetic fields at very low frequency: Evidence for a slowdown of the magnetization decay
http://hdl.handle.net/2268/180534
Titre: Measurements on magnetized GdBCO pellets subjected to small transverse ac magnetic fields at very low frequency: Evidence for a slowdown of the magnetization decay
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<br/>Auteur, co-auteur: Fagnard, Jean-François; Kirsch, Sébastien; Morita, Mitsuru; Teshima, Hidekazu; Vanderheyden, Benoît; Vanderbemden, Philippe
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<br/>Résumé: Due to their ability to trap large magnetic inductions, superconducting bulk materials can be used as powerful permanent magnets. The permanent magnetization of such materials, however, can be significantly affected by the application of several cycles of a transverse variable magnetic field. In this work, we study, at T = 77 K, the long term influence of transverse ac magnetic fields of small amplitudes (i.e. much smaller than the full penetration field) on the axial magnetization of a bulk single grain superconducting GdBCO pellet over a wide range of low frequencies (1 mHz–20 Hz). Thermocouples are placed against the pellet surface to probe possible self-heating of the material during the experiments. A high sensitivity cryogenic Hall probe is placed close to the surface to record the local magnetic induction normal to the surface.
The results show first that, for a given number of applied triangular transverse cycles, higher values of dBapp/dt induce smaller magnetization decays. An important feature of practical interest is that, after a very large number of cycles which cause the loss of a substantial amount of magnetization (depending on the amplitude and the frequency of the field), the rate of the magnetization decay goes back to its initial value, corresponding to the relaxation of the superconducting currents due to flux creep only. In the amplitude and frequency range investigated, the thermocouples measurements and a 2D magneto-thermal modelling show no evidence of sufficient self-heating to affect the magnetization so that the effect of the transverse magnetic field cycles on the trapped magnetic moment is only attributed to a redistribution of superconducting currents in the volume of the sample and not to a thermal effect.Noncollinear magnetism in post-perovskites from first-principles: Comparison between CaRhO3 and NaNiF3
http://hdl.handle.net/2268/180445
Titre: Noncollinear magnetism in post-perovskites from first-principles: Comparison between CaRhO3 and NaNiF3
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<br/>Auteur, co-auteur: Garcia Castro, Andrés Camilo; Romero, Aldo; Bousquet, Eric
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<br/>Résumé: Based on first-principles calculations, we study the noncollinear magnetism in the post-perovskites (pPv) phase of NaNiFinline image and CaRhOinline image crystals. We find that the magnetic canting is one of the most promising properties of pPv systems, which is allowed by symmetry in all the pPv crystals inline image with a magnetically active B-site. In the pPv phase of NaNiFinline image, which has a inline image antiferromagnetic ground state with a inline image ferromagnetic canting, we obtain a magnetic canting amplitude of about 0.1 inline imageatominline image, which is much larger than in the one obtained in CaRhOinline image (canting amplitude of 0.04 inline image). We also computed the exchange constants (inline image), the single-ion anisotropy (SIA) parameters and the anti-symmetric magnetic coupling described by the Dzyaloshinsky–Moriya (DM) interaction in order to scrutinize the origin of the magnetic canting. We find that the canting in NaNiFinline image is mainly due to the DM interaction, while in CaRhOinline image, both DM and SIA contribute to the magnetic canting. Our calculations thus confirm the noncollinear magnetic ground-state solution experimentally observed in both compounds and the calculated magnetic exchange interactions also confirm the quasi-2D magnetic behavior reported in pPv.Single-Molecule Sensing Using Carbon Nanotubes Decorated with Magnetic Clusters
http://hdl.handle.net/2268/180103
Titre: Single-Molecule Sensing Using Carbon Nanotubes Decorated with Magnetic Clusters
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<br/>Auteur, co-auteur: Zanolli, Zeila; Charlier, Jean-Christophe
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<br/>Résumé: First-principles and nonequilibrium Green's function techniques are used to investigate magnetism and spin-polarized quantum transport in metallic carbon nanotubes (CNT) decorated with transition metal (Ni_13, Pt_13) magnetic nanoclusters (NC). For small cluster sizes, the strong CNT-NC interaction induces spin-polarization in the CNT. The adsorption of a benzene molecule is found to drastically modify the CNT-NC magnetization. Such a magnetization change should be large enough to be detected via magnetic-AFM or SQUID magnetometry, hence suggesting a novel approach for single-molecule gas detection.Simulation of the elementary evolution operator with the motional states of an ion in an anharmonic trap
http://hdl.handle.net/2268/180084
Titre: Simulation of the elementary evolution operator with the motional states of an ion in an anharmonic trap
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<br/>Auteur, co-auteur: Santos, Ludovic; Justum, Yves; Vaeck, Nathalie; Desouter, Michèle
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<br/>Résumé: Following a recent proposal of L. Wang and D. Babikov, J. Chem. Phys. 137, 064301 (2012), we theoretically illustrate the possibility of using the motional states of a Cd+ ion trapped in a slightly anharmonic potential to simulate the single-particle time-dependent Schrödinger equation. The simulated wave packet is discretized on a spatial grid and the grid points are mapped on the ion motional states which define the qubit network. The localization probability at each grid point is obtained from the population in the corresponding motional state. The quantum gate is the elementary evolution operator corresponding to the time-dependent Schrödinger equation of the simulated system. The corresponding matrix can be estimated by any numerical algorithm. The radio-frequency field able to drive this unitary transformation among the qubit states of the ion is obtained by multi-target optimal control theory. The ion is assumed to be cooled in the ground motional state and the preliminary step consists in initializing the qubits with the amplitudes of the initial simulated wave packet. The time evolution of the localization probability at the grids points is then obtained by successive applications of the gate and reading out the motional state population. The gate field is always identical for a given simulated potential, only the field preparing the initial wave packet has to be optimized for different simulations. We check the stability of the simulation against decoherence due to fluctuating electric fields in the trap electrodes by applying dissipative Lindblad dynamics.