Unified understanding of tunneling ionization and stabilization of atomic hydrogen in circularly and linearly polarized intense laser fields

Journal Article · Thu Jul 15 04:00:00 EDT 2010 · Physical Review. A

DOI:https://doi.org/10.1103/PHYSREVA.82.013402· OSTI ID:21442928

Miyagi, Haruhide; Someda, Kiyohiko ^[1]

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1. Department of Basic Science, Graduate School of Arts and Sciences, University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8902 (Japan)

On the basis of the Floquet formalism, the ionization mechanisms of atomic hydrogen in circularly and linearly polarized intense laser fields are discussed. By using the complex scaling method in the velocity gauge, the pole positions of the scattering-matrix on the complex quasienergy Riemann surface are calculated, and pole trajectories with respect to the variation of the laser intensity are obtained. In the low-frequency regime, the pole trajectory exhibits a smooth ponderomotive energy shift in the case of circular polarization. In contrast, the smoothness is lost in the case of linear polarization. In the high-frequency regime, the pole trajectories exhibit the stabilization phenomenon for both the types of polarization. These observations are elucidated by a unified picture based on the analysis of the adiabatic potentials for the radial motion of the electron in the acceleration gauge. The ionization in the case of circular polarization of the low-frequency regime is governed by the electron tunneling through a barrier of a single adiabatic potential. The stabilization in the high-frequency regime can be explained by the change in the avoided crossings among the adiabatic potential curves. The transition between the different frequency regimes is explicable by the change in the structure of the adiabatic potentials. The difference caused by the type of polarization is ascribable to the difference in the space-time symmetry.

• OSTI ID: 21442928
• Journal Information: Physical Review. A, Journal Name: Physical Review. A Journal Issue: 1 Vol. 82; ISSN 1050-2947; ISSN PLRAAN
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
ATOM COLLISIONS
COLLISIONS
ELECTROMAGNETIC RADIATION
ELECTRONS
ELEMENTARY PARTICLES
ELEMENTS
FERMIONS
HYDROGEN
IONIZATION
LASER RADIATION
LEPTONS
NONMETALS
PHOTON COLLISIONS
PHOTON-ATOM COLLISIONS
POLARIZATION
PONDEROMOTIVE FORCE
POTENTIALS
RADIATIONS
RIEMANN SHEET
SPACE-TIME
STABILIZATION
TUNNEL EFFECT