Anyonic Excitations in Fast Rotating Bose Gases Revisited

The role of anyonic excitations in fast rotating harmonically trapped Bose gases in a fractional Quantum Hall state is examined. Standard Chern-Simons anyons as well as "non standard" anyons obtained from a statistical interaction having Maxwell-Chern-Simons dynamics and suitable non minimal coupling to matter are considered. Their respective ability to stabilize attractive Bose gases under fast rotation in the thermodynamical limit is studied. Stability can be obtained for standard anyons while for non standard anyons, stability requires that the range of the corresponding statistical interaction does not exceed the typical wavelenght of the atoms.Comment: 5 pages. Improved version to be published in Phys. Rev. A, including a physical discussion on relevant interactions and scattering regime together with implication on the nature of statistical interactio

On the Effective Action of Noncommutative Yang-Mills Theory

We compute here the Yang-Mills effective action on Moyal space by integrating over the scalar fields in a noncommutative scalar field theory with harmonic term, minimally coupled to an external gauge potential. We also explain the special regularisation scheme chosen here and give some links to the Schwinger parametric representation. Finally, we discuss the results obtained: a noncommutative possibly renormalisable Yang-Mills theory.Comment: 19 pages, 6 figures. At the occasion of the "International Conference on Noncommutative Geometry and Physics", April 2007, Orsay (France). To appear in J. Phys. Conf. Se

Vacuum configurations for renormalizable non-commutative scalar models

In this paper we find non-trivial vacuum states for the renormalizable non-commutative $\phi^4$ model. An associated linear sigma model is then considered. We further investigate the corresponding spontaneous symmetry breaking.Comment: 17 page

One-loop Beta Functions for the Orientable Non-commutative Gross-Neveu Model

We compute at the one-loop order the beta-functions for a renormalisable non-commutative analog of the Gross Neveu model defined on the Moyal plane. The calculation is performed within the so called x-space formalism. We find that this non-commutative field theory exhibits asymptotic freedom for any number of colors. The beta-function for the non-commutative counterpart of the Thirring model is found to be non vanishing.Comment: 16 pages, 9 figure

First case of childhood Takayasu arteritis with renal artery aneurysms

Takayasu arteritis is a large vessel systemic granulomatous vasculitis characterized by stenosis or obliteration of large and medium sized arteries. It commonly involves elastic arteries such as the aorta and its main branches. Renal artery involvement is rare and has not been reported in a child. We report a 12-year-old boy with Takayasu arteritis who developed severe hypertension, proteinuria, microscopic hematuria and renal dysfunction. Conventional angiography demonstrated aneurysms of both renal arteries and multiple microaneurysms of the superior mesenteric artery. This case report illustrates that the children with Takayasu arteritis can develop renal involvement resulting in hematuria, proteinuria and even renal failure

On the vacuum states for noncommutative gauge theory

Candidates for renormalisable gauge theory models on Moyal spaces constructed recently have non trivial vacua. We show that these models support vacuum states that are invariant under both global rotations and symplectic isomorphisms which form a global symmetry group for the action. We compute the explicit expression in the position space for these vacuum configurations in two and four dimensions.Comment: 20 page

Extended Generation Profile - E.B.I.C. Model

We have developed a model for the calculation of the induced current due to an electron beam with an extended profile. As well as the number of absorbed and diffuse electrons as a function of the depth, the generation profile takes into account the lateral diffusion and the effect of defects, dislocations and recombination surfaces. The expression from the Electron Beam Induced Current (EBIC) is obtained by solving the continuity equation in permanent regime by the Green function method. In the case of a Schottky diode Au/InP, obtained by ionic scattering followed by a quick thermal treatment, the induced current profile is compared to the theoretical profiles whose analytical expressions are given by Van Roosbroeck and Bresse. The experimental current profile, measured by S.E.M provided us with the calculation of the diffusion length of the minority carriers, $L_{\rm n}=1$ $\mu$m. The theoretical curve obtained from the proposed model is in good agreement with the experimental one for a surface recombination velocity of $10^{4}$ cm s$^{-1}$. Our results are found to be consistent with those obtained by other experimental techniques on the same samples.Nous avons développé un modèle de calcul du courant induit par un faisceau d'électrons avec un profil de génération élargi. Le profil de génération tient compte, en plus du nombre d'électrons absorbés et du nombre d'électrons diffusés en fonction de la profondeur, de la diffusion latérale (en prenant en considération la diffusion angulaire), de l'effet des défauts, des dislocations et de la recombinaison à la surface. L'expression analytique du courant induit E.B.I.C est déterminée par résolution de l'équation de continuité en régime permanent par la méthode des fonctions de Green. Le profil de courant induit obtenu dans le cas d'une diode Schottky Au/InP dopé p et fabriqué par implantation suivit d'un recuit, est comparé au profil de courant théorique dont l'expression analytique est explicité par Van Roosbroeck et Bresse. Le profil de courant expérimental, mesuré par un microscope électronique à balayage, nous a permis de calculer la longueur de diffusion des porteurs minoritaires $L_{\rm n}=1$ $\mu$m. La courbe théorique, tracée à partir du modèle proposé, est en bon accord avec la courbe expérimental pour une vitesse de recombinaison à la surface de $10^{4}$ cm s$^{-1}$. Ces résultats sont conformes avec ceux obtenus par d'autres techniques expérimentales sur les mêmes échantillons