title: Interaction of superintense laser pulses with relativistic ions.
abstract: At high intensities, three-step recollision processes driven by low frequency laser pulses, such as high-order harmonic generation and high-order above-threshold ionization, are normally severely suppressed by the magnetic-field component of the laser field. It is shown that this suppression is not severe, even for ponderomotive energies well above 10 keV, for multicharged ions moving at a sufficiently high relativistic velocity against a counterpropagating infrared laser pulse. Numerical results are presented for high-order harmonic emission by a single Ne9+ ion moving with a Lorentz factor gamma=15 against a Nd:glass laser beam. The calculations are done within a Coulomb-corrected nondipole strong field approximation. The approximation is tested by comparing with accurate results.
authors.affiliation: Department of Physics, University of Durham, Durham DH1 3LE, United Kingdom.
authors.forename: C C
authors.initials: CC
authors.lastname: Chirilă
authors.forename: C J
authors.initials: CJ
authors.lastname: Joachain
authors.forename: N J
authors.initials: NJ
authors.lastname: Kylstra
authors.forename: R M
authors.initials: RM
authors.lastname: Potvliege