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Indexed by:期刊论文

Date of Publication:2017-11-28

Journal:JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS

Included Journals:SCIE、EI

Volume:50

Issue:22

ISSN No.:0953-4075

Key Words:population transfer; femtosecond laser pulses; rotating wave approximation; adiabatic passage

Abstract:By utilizing the time-dependent wavepacket method, we studied the population transfer between the electronic states of the Na-2 molecule driven by femtosecond laser pulses. Three electronic states, X-1 Sigma(+)(g), A(1)Sigma(+)(u) and 2(1)Pi(g), are taken to be the initial, the intermediate and the target states, respectively. Two classes of calculations are performed for comparison: one is to invoke the rotating wave approximation (RWA), and the other is more accurate calculations without consideration of RWA (non-RWA). It is found that for this three-state-model, the RWA fails to describe the accurate population transfer process in femtosecond-pulse fields and that the adiabatic passage is hard to be constructed in the non-RWA calculations. Based on the non-RWA calculations, we determined a set of laser parameters, including the peak intensity, detuning, pulse duration and time delay, for efficient population transfer.