Search results for "Strong field"

showing 6 items of 16 documents

Theoretical Tools for the Description of Strong Field Laser-Molecule Interaction

2016

In this chapter, the main theoretical tools used in the work presented in the next two chapters on the laser control of the radiationless decay in pyrazine and of the tunneling dynamics in NHD\(_2\), are introduced.

PhysicsWork (thermodynamics)PyrazineStrong fieldLaserlaw.inventionchemistry.chemical_compoundGeometric phasechemistrylawMoleculeAtomic physicsRabi frequencyQuantum tunnelling
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Strong-field-ionization suppression by light-field control

2012

In recent attempts to control strong-field phenomena such as molecular dissociation, undesired ionization sometimes seriously limited the outcome. In this work we examine the capability of quantum optimal control theory to suppress the ionization by rational pulse shaping. Using a simple model system and the ground-state occupation as the target functional, we show that optimal control generally leads to a significant suppression of the ionization, although the fluence and the pulse length are kept fixed. In the low-frequency regime the ionization is reduced mainly by avoiding high peaks in the intensity and thus preventing tunneling. In contrast, at high frequencies in the extreme ultravio…

Physicsta114Ionization0103 physical sciencesStrong fieldAtomic physics010306 general physics01 natural sciences114 Physical sciencesAtomic and Molecular Physics and OpticsLight field010305 fluids & plasmas
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On the study of the laser filamentation process in rare gases under the strong field model : impacts of third harmonic generation and of the vicinity…

2017

Filamentation originates from the dynamic balance between linear and nonlinear effects, allowing the laser beam autostabilization over distances significantly greater than those predicted by linear optics laws. The aim of this thesis is to describe this phenomenon on rare gases under the strong field model, contrary to the commonly used perturbation model based on the weak field approximation. The influence of harmonics, so far neglected, is then revisited both at the microscopic level and at a propagation scale. It is shown, experimentally and with the support of numerical simulations, that a weak proportion of third harmonic is sufficient to strongly impact the filamentation dynamics, esp…

[PHYS.PHYS.PHYS-OPTICS] Physics [physics]/Physics [physics]/Optics [physics.optics][PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics]Kerr effectStrong fieldFilamentationChamp fortEffet Kerr
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Strong Field Iron(II) Complex Converted by Light into a Long-Lived High-Spin State

2000

chemistry.chemical_classificationchemistrySpin statesChemical physicsInorganic chemistryStrong fieldGeneral ChemistryCatalysisCoordination complexAngewandte Chemie
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Optically pumped Cs magnetometers enabling a high-sensitivity search for the neutron electric dipole moment

2020

An array of 16 laser-pumped scalar Cs magnetometers was part of the neutron electric dipole moment (nEDM) experiment taking data at the Paul Scherrer Institute in 2015 and 2016. It was deployed to measure the gradients of the experiment's magnetic field and to monitor their temporal evolution. The originality of the array lies in its compact design, in which a single near-infrared diode laser drives all magnetometers that are located in a high-vacuum chamber, with a selection of the sensors mounted on a high-voltage electrode. We describe details of the Cs sensors' construction and modes of operation, emphasizing the accuracy and sensitivity of the magnetic-field readout. We present two app…

experimental methodsAtomic Physics (physics.atom-ph)EXPERIMENTAL LIMITPhysics Atomic Molecular & Chemicalnucl-ex01 natural sciencesPhysics - Atomic PhysicsHigh Energy Physics - Experimentlaw.inventionHigh Energy Physics - Experiment (hep-ex)law[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]Nuclear Experiment (nucl-ex)n: spinNuclear ExperimentPhysicsn: electric momentPhysicsincluding interactions with strong fields and short pulsesMagnetic fieldAtomic and molecular processes in external fieldsPhysical SciencesParticle Physics - ExperimentNeutron electric dipole momentMagnetometerOther Fields of PhysicsFOS: Physical sciencesmagnetic field: gradient[PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex]physics.atom-phOptics0103 physical sciencesNeutronNuclear Physics - ExperimentSensitivity (control systems)010306 general physicsDiodeScience & Technology010308 nuclear & particles physicsbusiness.industryhep-exScalar (physics)OpticssensitivityLaser[PHYS.PHYS.PHYS-GEN-PH]Physics [physics]/Physics [physics]/General Physics [physics.gen-ph]laserfield strengthtime dependencebusinessexperimental results
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Strong field phenomena: Atoms, Molecules, Nanostructures.

nanostructureinteraction matter-radiationstrong fieldhhg; ati; multiphoton ionization; strong field; quantum rings; nanostructures; physics; interaction matter-radiation;multiphoton ionizationatiquantum ringhhgphysicSettore FIS/03 - Fisica Della Materia
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