Photoelectron Spectra of Four-Level Ladder Molecules: Effect of Femtosecond Laser Parameters

Abstract

Abstract: Autler-Townes (AT) splitting in photoelectron spectra of four-level ladder K₂ molecule driven by three laser pulses is investigated with time-dependent wave packet approach. Dependence of AT splitting on second laser pulse is studied. Photoelectron spectra show triple splitting with symmetric profiles in resonance, while triple splitting with asymmetric profiles is transformed into double splitting gradually in nonresnance. Three peaks shift to lower energy differently as laser wavelength increases. Splitting between two sideband peaks does not vary with laser wavelength, but increases with increasing laser intensity. These results are of importance for molecular spectroscopy. It stimulates theoretical studies from first principles and provides basis for realizing optical control of molecules.

Key words: time-dependent wave packet approach, four-level ladder K₂ molecule, photoelectron spectra, Autler-Townes splitting

CLC Number:

O644

LI Yuehua, GUO Wei. Photoelectron Spectra of Four-Level Ladder Molecules: Effect of Femtosecond Laser Parameters[J]. CHINESE JOURNAL OF COMPUTATIONAL PHYSICS, 2016, 33(4): 453-459.

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