arXiv subjects

Eric Charron

Publications and source records attributed to Eric Charron.

41 records · Page 3Linked to original sources

arXiv2007

Quantum phase gate and controlled entanglement with polar molecules

We propose an alternative scenario for the generation of entanglement between rotational quantum states of two polar molecules. This entanglement arises from dipole-dipole interaction, and is controlled by a sequence of laser pulses simultaneously exciting both molecules. We study the efficiency of the process, and discuss possible experimental implementations with cold molecules trapped in optical lattices or in solid matrices. Finally, various entanglement detection procedures are presented, and their suitability for these two physical situations is analyzed.

quant-ph↗

arXiv2006

Phase information revealed by interferences in the ionization of rotational wave packets

Time-resolved photoelectron spectra are proposed for the measurement of classical information recorded in the quantum phases of a molecular rotational wave packet. Taking Li2 as a prototypical system, we show that an interference arises from the electron-nuclei entanglement induced by the molecular anisotropy. This phenomenon is used to transfer the information that was stored initially in the nuclear rotational degree of freedom into the electronic degree of freedom.

quant-ph↗

arXiv2006

Theoretical study of a cold atom beam splitter

A theoretical model is presented for the study of the dynamics of a cold atomic cloud falling in the gravity ﬁeld in the presence of two crossing dipole guides. The cloud is split between the two branches of this laser guide, and we compare experimental measurements of the splitting efﬁciency with semiclassical simulations. We then explore the possibilities of optimization of this beam splitter. Our numerical study also gives access to detailed information, such as the atom temperature after the splitting.

quant-ph↗

arXiv2006

Spatial variation of the laser fields and electron dynamics at a gas-solid interface

In the long wavelength domain, typically for wavelengths lambda > 100 angstroms, the laser fields are usually taken as independent of the spatial coordinate. However, at the gas-solid interface the electron density of the material and the incident laser fields vary sharply on a scale of few angstroms. Instead of solving Maxwell equations, we present here a theoretical model, called Electromagnetic Fields from Electron Density (EMFED), generating a continuous vector potential from phenomenological relations combining the unperturbed electron density of the material system, the material constants and the laws of optics. As an application of this model, we calculate in a time dependent approach the transition probability and the induced current density between the last bulk state below the Fermi energy and the first image state of a Cu(001) metallic surface. These observables are significantly modified by the spatial variation of the vector potential at the surface. The Coulomb gauge condition, fullfilled everywhere else, breaks down near the surface. The difference between the s- and p- polarizations of the laser field partially unravels this effect.

cond-mat.other↗

arXiv1995

Coherent Control of Isotope Separation in HD+ Photodissociation by Strong Fields

The photodissociation of the HD+ molecular ion in intense short- pulsed linearly polarized laser fields is studied using a time- dependent wave-packet approach where molecular rotation is fully included. We show that applying a coherent superposition of the fundamental radiation with its second harmonic can lead to asymmetries in the fragment angular distributions, with significant differences between the hydrogen and deuterium distributions in the long wavelength domain where the permanent dipole is most efficient. This effect is used to induce an appreciable isotope separation.

chem-ph↗