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Indexed by:期刊论文

Date of Publication:2013-04-05

Journal:PHYSICAL REVIEW A

Included Journals:SCIE、EI、Scopus

Volume:87

Issue:4

ISSN No.:1050-2947

Abstract:The interference minimum in the high-order harmonic spectrum of H-2(+) is studied by solving the full three-dimensional time-dependent Schrodinger equation for the electronic motion keeping the nuclei fixed. The two-center interference model works well when the internuclear distance is around its equilibrium value where also recombination to the (2)Sigma(+)(g) (1s sigma(g)) ground state dominates. As the internuclear distance is increased, the minimum first shifts in position compared with the prediction of the two-center interference model and subsequently disappears. These effects are caused by the excited (2)Sigma(+)(u) (2p sigma(u)) state, partly due to the interference between the amplitudes of recombination to the ground and excited states, but also partly due to the signal associated with recombination to the excited state alone. We find that at internuclear distances beyond R similar or equal to 3 a.u. the signal close to the harmonic cutoff may be completely dominated by recombination into the excited (2)Sigma(+)(u) (2p sigma(u)) state. DOI: 10.1103/PhysRevA.87.043404