| Autor: |
Fuks, J. I., Helbig, N., Tokatly, I. V., Rubio, A. |
| Rok vydání: |
2011 |
| Předmět: |
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| Zdroj: |
Phys. Rev. B 84, 075107 (2011) |
| Druh dokumentu: |
Working Paper |
| DOI: |
10.1103/PhysRevB.84.075107 |
| Popis: |
Through the exact solution of a two-electron system interacting with a monochromatic laser we prove that all adiabatic density functionals within time-dependent density-functional theory are not able to discern between resonant and non-resonant (detuned) Rabi oscillations. This is rationalized in terms of a fictitious dynamical exchange-correlation (xc) detuning of the resonance while the laser is acting. The non-linear dynamics of the Kohn-Sham system shows the characteristic features of detuned Rabi oscillations even if the exact resonant frequency is used. We identify the source of this error in a contribution from the xc-functional to the non-linear equations describing the electron dynamics in an effective two-level system. The constraint of preventing the detuning introduces a new strong condition to be satisfied by approximate xc-functionals. |
| Databáze: |
arXiv |
| Externí odkaz: |
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