Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Physica Scripta

Light-Induced States of Atoms in Intense Laser Fields

R. M. Potvliege

Published Jan 1, 2003• 7 citations
Publisher

Abstract

In a broad sense, light-induced atomic states are decaying bound states that exist in sufficiently strong laser fields but cannot be adiabatically followed to zero intensity as physical quasistationary states. Some of them have no counterpart in the field-free bound-state spectrum. The paper contains a short review of the literature concerning this topic. It addresses two issues: the origin of the light-induced states in Floquet theory, and their relevance.

DOI
10.1238/physica.regular.068ac0018

Related papers

Laser-induced bound and metastable states in bound-continuum systems

Kai‐Shue Lam, Thomas F. George

A monochromatic laser is shown to be capable of inducing a bound state and multiple metastable states not originally present in the field-free spectrum of a bound-continuum system. For the bound state to exist, the field intensity must be larger than a certain frequency-dependent critical value. The widths of the metastable states are found to be in general proportional to renormalized field intensities rather than the physical field intensity. The energies can be classified as being in the metastable or unstable regimes, depending on whether the observed widths are smaller or larger than the corresponding ``bare'' widths predicted by perturbation theory. The relation of the Fano or laser-induced ``autoionization'' states to the scattering states is also demonstrated.

Physical Review A•Apr 1, 1986•9 citations

Laser-induced collective binding in two-electron systems

H. Klar, P. Zoller, Mikhail Vladimirovich Fedorov

Doubly excited states of atoms in an intense laser field can be described approximately within the framework of an adiabatic separation method with the use of hyperspherical coordinates. Under suitable conditions, depending on the zero-field atomic spectrum and on the laser field, new laser-induced two-electron resonances appear.

Physical Review A•Jul 1, 1984•5 citations

Dipole and quadrupole forces exerted on atoms in laser fields: The nonperturbative approach

Milan Šindelka, Nimrod Moiseyev, Lorenz S. Cederbaum

Manipulation of cold atoms by lasers has so far been studied solely within the framework of the conventional dipole approximation, and the atom-light interaction has been treated using low order perturbation theory. Laser control of atomic motions has been ascribed exclusively to the corresponding light-induced dipole forces. In this work, we present a general theory to derive the potential experienced by an atom in a monochromatic laser field in a context analogous to the Born-Oppenheimer approximation for molecules in the field-free case. The formulation goes beyond the dipole approximation and gives rise to the field-atom coupling potential terms which so far have not been taken into consideration in theoretical or experimental studies. Contrary to conventional approaches, our method is based upon the many electron Floquet theory and remains valid also for high intensity laser fields (i.e., for a strongly nonperturbative atom-light interaction). As an illustration of the developed theory, we investigate the trapping of cold atoms in optical lattices. We find that for some atoms for specific laser parameters, despite the absence of the dipole force, the laser trapping is still possible due to the electric quadrupole forces. Namely, we show that by using realistic laser parameters one can form a quadrupole optical lattice which is sufficiently strong to trap Ca and Na atoms.

Physical Review A•Nov 29, 2006•13 citations

On the relation between cavity-dressed states, Floquet states, RWA and semiclassical models

S. Guérin, F Monti, J.-C. Dupont +1 more

We show that Floquet states can be constructed as strong-field limits of cavity-dressed states. The interaction between laser beams propagating outside the cavity with atoms or molecules are described by Floquet states, constructed from dressed states of average photon number quantized in a cavity of volume V, by taking the limit , , while keeping the photon density constant. Thus, Floquet theory can be seen as a fully quantum-mechanical model in the sense that it describes the photon exchanges between matter and radiation containing a large amount of photons. We discuss in this context adiabatic Floquet theory to treat a slow time dependence of the laser amplitude, to describe pulses, and of its frequency (chirping).

Journal of Physics A Mathematical and General•Oct 21, 1997•65 citations

Floquet theory

C. J. Joachain, Niels J. Kylstra, R. M. Potvliege

In this chapter,we shall analyze the particular case of an atom interacting with a laser pulse whose duration is sufficiently long, so that the evolution of the atom in the laser field is adiabatic. When this condition is fulfilled, the atom can be considered to interact with a monochromatic laser field. As a consequence, the Hamiltonian of the system is periodic in time, and the Floquet theory [1] can be used to solve the time-dependent Schrödinger equation (TDSE) non-perturbatively. We begin in Section 4.1 by considering the Hermitian Floquet theory. We first derive the Floquet theorem for a monochromatic, spatially homogeneous laser field and show that the solutions of the TDSE correspond to dressed states having real quasi-energies , which can be obtained by solving an infinite system of time-independent coupled equations. We then generalize the Floquet theory to multicolor laser fields and to “non-dipole” laser fields which are not spatially homogeneous. In Section 4.2, the Floquet theory is applied to study the dynamics of a model atom having M discrete levels interacting with a monochromatic laser field. In this case, the coupling between the bound and continuum atomic states is neglected.We analyze the relationship between the Floquet theory and the rotating wave approximation, and examine the perturbative limit of the Floquet theory. We also consider the population transfer between Floquet dressed states.

Cambridge University Press eBooks•Dec 15, 2011•0 citations

Floquet theory for atomic light-shift engineering with near-resonant polychromatic fields

Simon Coop, Silvana Palacios, Pau Gomez +3 more

Optical trapping of atoms employs high-intensity fields that necessarily alter atomic level structure. The calculation of light shifts by perturbation theory fails for scenarios that arise, for example, when the trapping light is near an excited-state transition or for polychromatic fields. We show here that non-perturbative methods based on Floquet’s theorem elegantly handle such scenarios. We compare our calculation to precision absorption spectroscopy on cold 87Rb atoms in a bichromatic optical dipole trap at 1560 + 1529 nm. Proximity to excited-state resonances induces highly nonlinear level shifts, providing a strong test of theory. The good theory-experiment agreement suggests a new method for accurate measurements of excited-state electric-dipole matrix elements and a precision tool for engineering custom atomic level structures.

Optics Express•Dec 14, 2017•15 citations
In a broad sense, light-induced atomic states are decaying bound states that exist in sufficiently strong laser fields but cannot be adiabatically followed to zero intensity as physical quasistationary states. Some of them have no counterpart in the field-free bound-state spectrum. The paper contains a short review of the literature concerning this topic. It addresses two issues: the origin of the light-induced states in Floquet theory, and their relevance.
A monochromatic laser is shown to be capable of inducing a bound state and multiple metastable states not originally present in the field-free spectrum of a bound-continuum system. For the bound state to exist, the field intensity must be larger than a certain frequency-dependent critical value. The widths of the metastable states are found to be in general proportional to renormalized field intensities rather than the physical field intensity. The energies can be classified as being in the metastable or unstable regimes, depending on whether the observed widths are smaller or larger than the corresponding ``bare'' widths predicted by perturbation theory. The relation of the Fano or laser-induced ``autoionization'' states to the scattering states is also demonstrated.
Manipulation of cold atoms by lasers has so far been studied solely within the framework of the conventional dipole approximation, and the atom-light interaction has been treated using low order perturbation theory. Laser control of atomic motions has been ascribed exclusively to the corresponding light-induced dipole forces. In this work, we present a general theory to derive the potential experienced by an atom in a monochromatic laser field in a context analogous to the Born-Oppenheimer approximation for molecules in the field-free case. The formulation goes beyond the dipole approximation and gives rise to the field-atom coupling potential terms which so far have not been taken into consideration in theoretical or experimental studies. Contrary to conventional approaches, our method is based upon the many electron Floquet theory and remains valid also for high intensity laser fields (i.e., for a strongly nonperturbative atom-light interaction). As an illustration of the developed theory, we investigate the trapping of cold atoms in optical lattices. We find that for some atoms for specific laser parameters, despite the absence of the dipole force, the laser trapping is still possible due to the electric quadrupole forces. Namely, we show that by using realistic laser parameters one can form a quadrupole optical lattice which is sufficiently strong to trap Ca and Na atoms.
We show that Floquet states can be constructed as strong-field limits of cavity-dressed states. The interaction between laser beams propagating outside the cavity with atoms or molecules are described by Floquet states, constructed from dressed states of average photon number quantized in a cavity of volume V, by taking the limit , , while keeping the photon density constant. Thus, Floquet theory can be seen as a fully quantum-mechanical model in the sense that it describes the photon exchanges between matter and radiation containing a large amount of photons. We discuss in this context adiabatic Floquet theory to treat a slow time dependence of the laser amplitude, to describe pulses, and of its frequency (chirping).
In this chapter,we shall analyze the particular case of an atom interacting with a laser pulse whose duration is sufficiently long, so that the evolution of the atom in the laser field is adiabatic. When this condition is fulfilled, the atom can be considered to interact with a monochromatic laser field. As a consequence, the Hamiltonian of the system is periodic in time, and the Floquet theory [1] can be used to solve the time-dependent Schrödinger equation (TDSE) non-perturbatively. We begin in Section 4.1 by considering the Hermitian Floquet theory. We first derive the Floquet theorem for a monochromatic, spatially homogeneous laser field and show that the solutions of the TDSE correspond to dressed states having real quasi-energies , which can be obtained by solving an infinite system of time-independent coupled equations. We then generalize the Floquet theory to multicolor laser fields and to “non-dipole” laser fields which are not spatially homogeneous. In Section 4.2, the Floquet theory is applied to study the dynamics of a model atom having M discrete levels interacting with a monochromatic laser field. In this case, the coupling between the bound and continuum atomic states is neglected.We analyze the relationship between the Floquet theory and the rotating wave approximation, and examine the perturbative limit of the Floquet theory. We also consider the population transfer between Floquet dressed states.
Optical trapping of atoms employs high-intensity fields that necessarily alter atomic level structure. The calculation of light shifts by perturbation theory fails for scenarios that arise, for example, when the trapping light is near an excited-state transition or for polychromatic fields. We show here that non-perturbative methods based on Floquet’s theorem elegantly handle such scenarios. We compare our calculation to precision absorption spectroscopy on cold 87Rb atoms in a bichromatic optical dipole trap at 1560 + 1529 nm. Proximity to excited-state resonances induces highly nonlinear level shifts, providing a strong test of theory. The good theory-experiment agreement suggests a new method for accurate measurements of excited-state electric-dipole matrix elements and a precision tool for engineering custom atomic level structures.