Controlling atomic structures and photoabsorption processes by an infrared laser

Journal Article · Tue Jun 15 04:00:00 EDT 2010 · Physical Review. A

DOI:https://doi.org/10.1103/PHYSREVA.81.063403· OSTI ID:21437912

Tong, X M ^[1]; Toshima, N ^[1]

---

1. Institute of Materials Science, Graduate School of Pure and Applied Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8573 (Japan)

We propose a theoretical method to calculate the infrared (IR) laser-assisted photoabsorption cross sections over a broad energy range by a single calculation. In this method we define an initial wave function as the product of the dipole operator and the atomic ground state, propagate the initial wave function in the IR laser field with different initial phases, then calculate the generalized autocorrelation function, which is defined as the averaged value of the autocorrelation function over the initial phase from 0 to 2{pi} (or one IR optical cycle). The IR laser-assisted photoabsorption cross sections are obtained by the Fourier transform of the generalized autocorrelation function. We apply this method to study the IR laser-assisted photoabsorption of He atoms. From the simulation results, we see that the IR laser field affects not only the resonant position but also the lifetime or the width of the bound states. This photoabsorption cross section is an important quantity to analyze the IR-laser-assisted dynamical processes by an attosecond pulse, a pulse train, or a free-electron laser.

• OSTI ID: 21437912
• Journal Information: Physical Review. A, Journal Name: Physical Review. A Journal Issue: 6 Vol. 81; ISSN 1050-2947; ISSN PLRAAN
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
ATOM COLLISIONS
COLLISIONS
COMPUTERIZED SIMULATION
CORRELATION FUNCTIONS
CROSS SECTIONS
DIPOLES
ELECTROMAGNETIC RADIATION
ELEMENTS
FLUIDS
FOURIER TRANSFORMATION
FREE ELECTRON LASERS
FUNCTIONS
GASES
HELIUM
INFRARED RADIATION
INTEGRAL TRANSFORMATIONS
LASER RADIATION
LASERS
LIFETIME
MULTIPOLES
NONMETALS
PHOTON COLLISIONS
PHOTON-ATOM COLLISIONS
PULSES
RADIATIONS
RARE GASES
SIMULATION
TRANSFORMATIONS
WAVE FUNCTIONS