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arXiv · 0906.1556

Rabi Oscillations and Few-Level Approximations in Time-Dependent Density Functional Theory

M. Ruggenthaler·D. Bauer
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Abstract

The resonant interaction of laser light with atoms is analyzed from the time-dependent density functional theory perspective using a model Helium atom which can be solved exactly. It is found that in exact-exchange approximation the time-dependent dipole shows Rabi-type oscillations of its amplitude. However, the time-dependent density itself is not well described. These seemingly contradictory findings are analyzed. The Rabi-type oscillations are found to be essentially of classical origin. The incompatibility of time-dependent density functional theory with few-level approximations for the description of resonant dynamics is discussed.

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M. Ruggenthaler, D. Bauer. 2009-06-08. Rabi Oscillations and Few-Level Approximations in Time-Dependent Density Functional Theory. https://doi.org/10.1103/physrevlett.102.233001

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