Asymmetry of above-threshold ionization of metal clusters in two-color laser fields: A time-dependent density-functional study

Journal Article · Tue Jun 01 04:00:00 EDT 2004 · Physical Review. A

DOI:https://doi.org/10.1103/PhysRevA.69.063415· OSTI ID:20643793

Nguyen, H S; Bandrauk, A D; Ullrich, C A ^[1]

---

1. Laboratoire de Chimie Theorique, Faculte des Sciences, Universite de Sherbrooke, Sherbrooke, Quebec J1K 2R1 (Canada)

Above threshold ionization (ATI) spectra of small metal clusters (e.g., Na{sub 4} and Na{sub 4}{sup +}) are calculated numerically using a spherical jellium model and time-dependent density functional theory for two-color (1064 and 532 nm) ultrashort (25 fs) laser pulses as a function of phase difference between the two fields. ATI spectra and ionized electron fluxes are obtained in the two opposite directions of the linearly polarized laser fields. The asymmetry, defined as the difference in electron yield, is shown to depend strongly on the carrier-envelope phase of the second-harmonic (2{omega}) field. The ATI spectra allow one to identify the range of kinetic energies of the ionized electrons where the asymmetry mainly occurs. Comparisons are made between calculations with and without self-interaction correction and also with previous exact numerical solutions of the one-electron systems H and H{sub 2}{sup +} [A. D. Bandrauk and S. Chelkowski, Phys. Rev. Lett. 84, 3562 (2000)] where such asymmetry effects had first been observed. We find that ATI spectra in the clusters generally have much longer energy plateaus than in previously studied one-electron systems, with cutoffs up to 30-40 times the ponderomotive energy U{sub p}. In high-harmonic generation spectra, on the other hand, no extended plateaus are observed.

• OSTI ID: 20643793
• Journal Information: Physical Review. A, Journal Name: Physical Review. A Journal Issue: 6 Vol. 69; ISSN 1050-2947; ISSN PLRAAN
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
ASYMMETRY
ATOMIC CLUSTERS
ATOMS
COMPARATIVE EVALUATIONS
CORRECTIONS
DENSITY FUNCTIONAL METHOD
ELECTRONS
HARMONIC GENERATION
HYDROGEN
HYDROGEN IONS 2 PLUS
KINETIC ENERGY
LASER RADIATION
MOLECULES
NUMERICAL SOLUTION
PHOTOIONIZATION
PHOTON-ATOM COLLISIONS
PONDEROMOTIVE FORCE
PULSES
SODIUM
SPECTRA
SPHERICAL CONFIGURATION
TIME DEPENDENCE