Search results for "résonances."

showing 3 items of 3 documents

Study of optical and magneto processes in Rb atomic vapor layer of nanometric thickness

2012

Using a narrow-band resonant fluorescence spectra from a nano-cell with a thickness of L= [lambda]/2, and VSOP resonances formed at a thickness L =[lambda] ([lambda] is the wavelength of the resonant radiation), for the first time it was experimentally investigated the behaviour of the frequency and intensity (transition probabilities) of the atomic hyperfine structure transitions between the 85Rb, 87Rb, D1 and D2 lines Zeeman sublevels in external magnetic fields in range 5 - 7000G. The behaviour of tens of previously unstudied atomic transitions was analyzed and it is demonstrated that the intensities of these lines can both greatly increase, and decrease (tenfold). For the first time it …

Gaz tamponπ et ơ- polarizations of the laser radiationCoherent Dicke narrowing[PHYS.COND.CM-GEN] Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other]High resolution spectroscopyRécissement Dicke cohérentRb hyperfine structureπ et ơ- du rayonnement laserStructure hyperfine RbCellules multi-régions combinéesRésonances VSOPTransitions "interdites''[ PHYS.COND.CM-GEN ] Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other]Nano-cellsZeeman effectDiode laserNano-cellulesEffet ZeemanƠ+Polarisations Ơ+"Forbidden'' transitions[PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other]Combined multi-region cellsBuffer gasVSOP resonancesSpectroscopie à haute résolution
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STUDY OF THE INTERNAL DYNAMICS OF NON PLANAR PYRAMIDAL MOLECULES IN VIBRATIONALY VERY EXCITED STATES.

2007

From the U (p+1) formalism, we built a Hamiltonian adapted to the stretching modes of nonplanar XY3 molecules having the C3v group of geometrical invariance. This Hamiltonian is then coupled with two possible Hamiltonians describing the bending modes of these molecular system: a) based on the U (p+1) approach, a bending Hamiltonian is developed and the interaction between the bending and the stretching modes is taking into account through adapted 2:1 resonance coupling operator defined as a Us(4) x Ub(4) enveloping algebra operator ; b) based on the standard normal modes formalism, a bending modes Hamiltonian is expanded and the 2:1 interaction is taken into account as a tensorial product o…

Spectroscopie moléculaire[ PHYS.PHYS.PHYS-ATOM-PH ] Physics [physics]/Physics [physics]/Atomic Physics [physics.atom-ph]phosphinerésonances.approche algébriquevibrationstibine[PHYS.PHYS.PHYS-ATOM-PH] Physics [physics]/Physics [physics]/Atomic Physics [physics.atom-ph]algebraic approachMolecular spectroscopyarsine
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INSTABILITY OF HAMILTONIAN SYSTEMS IN THE SENSE OF CHIRIKOV AND BIFURCATION IN A NON LINEAR EVOLUTION PROBLEM EMANATING FROM PHYSICS

2004

We prove the existence of a minimal geometrico-dynamical condition to create hyperbolicity in section in the vicinity of a transversal homoclinic partially hyperbolic torus in a near integrable Hamiltonian system with three degrees of freedom. We deduce in this context a generalization of the Easton's theorem of symbolic dynamics. Then we give the optimal estimation of the Arnold diffusion time along a transition chain in the initially hyperbolic Hamiltonian systems with three degrees of freedom with a surrounding chain of hyperbolic periodic orbits .In a second part, we describe geometrically a mechanism of diffusion studied by Chirikov in a near integrable Hamiltonian system with three de…

[ MATH ] Mathematics [math]dynamique symboliquehyperbolicitymodulational instabilityNavier Stokespartially hyperbolic tori[MATH] Mathematics [math]amplitude equationschevauchement de résonancescenter manifoldconvection mixte –hyperbolicitéoverlapping resonancessymbolic dynamicséquations d'amplitudesystèmes Hamiltoniensbifurcationinstabilité modulationnellevariété centraleHamiltonian systems[MATH]Mathematics [math]tores partiellement hyperboliquesmixed convection
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