0000000000514379
AUTHOR
Claude Leroy
showing 34 related works from this author
Landau‐Zener transition for association of an atomic Bose‐Einstein condensate with interparticle elastic interactions included.
2008
On the Study of the Very High Excited Vibrational Levels of the Pyramidal Molecules
2006
Etude des états vibrationnels très excités des molécules de type XY3. Application à la phosphine et à l'arsine.
2007
Study of Resonance Interactions and Splittings in the PH3 Molecule : v1, v3, v2+v4 and 2v4 Bands
2002
Etude des Etats Vibrationnels Très Excités des Molécules Pyramidales Non Planes.
2006
Analysis of high excited "hot" bands of the SO2 molecule
2011
The main goal of the present study is to analyse rotational structures of highly excited "hot" vibrational bands, v1+2v2-v2 and 2v2+v3-v2, v2+3v3-v2 and 2v1+v2+v3-v2, and v2+2v3-v2. All of these bands are located in the region of considerably stronger bands, v1 + v2 and v2 + v3, 3v3 and 2v1+v3, and 2v3, respectively . On that reason, as the first step of analysis, we made assignments of transitions belonging to these strong bands. As the result of analysis, we were able to assign three times more transitions to the bands v1 + v2 , v2 + v3, and 3v3 (3360 transitions with Jmax. = 78 and Kmax.a = 27 to the band v1 + v2, and 2380 transitions with Jmax. = 69 and Kmax.a = 24 to the band v2 + v3, …
Symmetrized rovibrational local states for triply degenerate modes of spherical molecules: application to intensity calculations in the nu3 ladder
1998
International audience; XY6 octahedral molecules, like SF6, WF6 and UF6, reveal a localized behaviour in the excited states of their stretching mode nu3. This character may be described through the G U (3) K3 O_h group chain (Boujut, V., Michelot, F., and Leroy, C., 1998, Molec. Phys., 93, 879). In this paper, we extend our previous theoretical developments by: the construction of a symmetrized local rovibrational basis, denoted |n;J_eta|K|Gamma mu>, well adapted to the study of the(n 00) states of the nu3 ladder the introduction of an approximate infrared intensity model for the transitions (000) (n 00) with n odd. We believe that the simplicity of the analytic expressions obtained in each…
Algebraic study of pyramidal XY3 molecules in vibrationally high excited states.
2010
National audience
Study of atomic Vapour Layers of Nanometric Thickness and Atom-Surface Interaction
2007
The U(p+1) Formalism Applied to The Vibrational Hamiltonians of Nonlinear AB2 Molecules
2000
Algebraic Approach to Vibrational Spectra of Stibine Molecule
2002
International audience
Algebraic Hamiltonian Adapted to Strech-Bend Coupling in the Stibine Molecule.
2003
On the "expanded local mode" approach applied to the methane molecule
2011
Methane (CH4 ) is one of the main prototypical hydrocarbons and is of great importance in a variety of applications ranging from our understanding of the chemical bonding, structure and quantum dynamics, reaction kinetics to geology, astrophysics, atmospheric and environmental science. On that reason, during more than five last decades both the vibrational and ro-vibrational spectra of methane were a subject of numerous studies (see, for example, M.Hippler and M.Quack, J. Chem. Phys. 116 (2002) 6045. and H.M.Niederer, S.Albert, S.Bauerecker, V.Boudon, J.P.Champion and M.Quack, Chimia 62 (2008) 273 where extensive references to spectroscopic and theoretical works can be found, the complete, …
Peculiarities of Electromagnetically-Induced Transparency (EIT) in Extremely Thin Cell of alkali metal atomic vapour.
2006
Quantitative spectroscopy of Rb atoms in a strong magnetic field based on submicron thin vapor cell
2010
Influence of Unequal Oscillator Strenghts on Stimulated Raman Adiabatic Passage through Bright State
2011
The problem of the coherent control of atomic states, preparation of atoms in a stable superposition state, and atomic population transfer has attracted much attention in the last decade. One of the main motivations is associated with the rapid development of the field of quantum computing. One of the key problems of quantum information processing is the construction of given coherent superposition atomic states in a macroscopic volume. Stimulated Raman adiabatic passage (STIRAP) [1] is considered to be the most common method for atomic population transfer in quantum systems. Being analyzed in detail on various quantum systems from both theoretical and experimental points of view, this meth…
High Resolution Study of Some Doubly Excited Vibrational States of PH2D: The v1+v2, v2+v5, v2+v3 and v2+v6 Bands
2003
Electromanetically Induced Resonances in Sub-Micron Thin Rb-Vapor Layer
2006
Laser Pulse Storage and Population Transfer in Solids Without Electromagnetically Induced Transparency
2008
Rovibrational interactions in the local-mode limit. The (n000) stretching overtone bands of spherical tops.
1993
Storage of optical pulses in solids despite fast relaxation.
2008
Fermi-type interaction in molecular and atomic Hamiltonians. Application to molecular systems and Bose-Einstein condensates.
2008
International audience; We present a simple prescription to build phenomenological Hamiltonians describing Fermi-type interactions and apply the developed formalism to two distinct physical systems. First, in a very simple way, we derive equations describing time dynamics of two coherently coupled Bose-Einstein condensates. Further, for bent XY2 molecules, we reproduce all the experimental data with an excellent precision.
Unitary Approach to Vibrational Spectra of Polyatomic Molecules: Generalized Infrared Intensity Model.
1996
high contrast sub-natural resonance of increased absorption formed in cell filled with Rb and buffer gas
2011
On the SPGF approach in asymmetric top molecules: application to the hydrogen sulfide.
2007
Approche Unitaire en Spectroscopie Moléculaire
1996
International audience
Landau-Zener Transition for Association of an Atomic Bose-Einstein Condensate With Inter-Particle Elastic Interactions Included
2008
International audience; We study strong coupling limit of the non-linear Landau-Zener transition at coherent photo- and magneto-association of cold atoms, focusing on the role of the elastic interspecies scatterings. Using an exact third-order nonlinear differential equation for the molecular state probability, we develop a nontrivial version of the strained parameter method which enables us to construct a highly accurate and simple analytic approximation describing time dynamics of the coupled atom-molecular system.
Narrow and contrast resonance of increased absorption in Λ-system observed in Rb cell with buffer gas
2009
International audience; We report observation of a narrow (sub-natural) and high-contrast resonance of increased absorption (“bright” resonance) in Rb cell with Ne buffer gas under previously unexplored experimental conditions for coupling and probe radiation configuration. The coupling laser-stabilized frequency is detuned by ~3 GHz from 5S1/2, Fg=3 → 5P3/2, Fe=2,3,4 transitions, while the probe laser frequency is scanned across these transitions. We believe the bright resonance formation, occurring when the probe laser frequency is blue-shifted from the coupling frequency by a value of the ground state hyperfine splitting, is caused predominantly by a 2-photon absorption of the probe radi…
Calculation of modification of alkali metal atomic transition probability in strong external magnetic field and its application
2010
International audience; Interaction of alkali atoms with external magnetic field induced a splitting and a shift of their energy levels. We have study this interaction for external field from 0 to 5000 Gauss when the alkali vapor is confined in submicron thin vapor cell with thickness L = λ/2. Rubidium and Sodium vapors have been studied. The Hamiltonian can be expressed as the sum of the unperturbated atomic Hamiltonian and the so-called Zeeman Hamiltonian. The probability of a transition, induced by the laser electric field is proportional to the square of the transfer coefficients modified by the presence of the magnetic field. We will show that the strong nonlinearity of the transition …
high-spatial-resolution monitoring of strong magnetic field using Rb nano-thin-cell
2011
The U(p+1) Formalism Applied to The Vibrational Hamiltonians of Nonlinear ABC Molecules
2000
Absorption, fluorescence and EIT processes in the extremely thin cell filled with Rb and buffer gas neon
2008
International audience; Comparison of the absorption and fluorescence in the nanocell (or so called extremely thin cell) filled with pure Rb with another one filled with Rb and Neon gas is provided. The effect of the collapse and revival of Dicke-type narrowing is still observable for thickness L=lambda/2, and lambda, where lambda , is a resonant laser wavelength either 780 nm, or 795 nm (for Rb, D2 or D1 line). For L= so called velocity selective optical pumping (VSOP) resonance located at the atomic transition is still observable, while the linewidth is increased by 4 times in comparison with that obtained in the pure Rb nanocell. Comparison with the theory is presented. Electromagnetic…
Study of atomic vapor layers of nanometric thickness and atom-surface interaction
2007
International audience