Population inversion in a multilevel system: A model study

Bjarne Amstrup, András Lörincz, Stuart A. Rice

Research output: Contribution to journalArticle

17 Citations (Scopus)

Abstract

For most isolated molecules, the generation of a π-pulse which will create complete inversion of the population of two electronic states is impossible because the rotational contribution to the transition dipole moment is an explicit function of the projection of the total angular momentum along the electric field axis. It is, however, possible to obtain nearly complete inversion by use of phase- and amplitude-modulated pulses; we show examples of such inversion with scaled and swept hyperbolic secant pulses. We report the results of pulse shape calculations for model systems with one and eight transition dipole moments. The pulse shaping is based on optimal control theory, where both the time-dependent Schrödinger equation and the pulse energy are used as constraints and where the deviation of the pulse shape from a swept hyperbolic secant form is treated as a cost to be minimized. This use of a time-dependent penalty function is intended to bias the calculated optimal pulse shape in the direction of experimentally producible pulse shapes. The method is applied to a model system with two displaced potential energy surfaces which support harmonic vibrational motion.

Original languageEnglish
Pages (from-to)6175-6183
Number of pages9
JournalJournal of Physical Chemistry
Volume97
Issue number23
Publication statusPublished - 1993

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population inversion
Dipole moment
Pulse shaping
Potential energy surfaces
Angular momentum
Electronic states
pulses
Control theory
Electric fields
Molecules
inversions
Costs
dipole moments
penalty function
control theory
optimal control
angular momentum
projection
potential energy
costs

ASJC Scopus subject areas

  • Physical and Theoretical Chemistry

Cite this

Population inversion in a multilevel system : A model study. / Amstrup, Bjarne; Lörincz, András; Rice, Stuart A.

In: Journal of Physical Chemistry, Vol. 97, No. 23, 1993, p. 6175-6183.

Research output: Contribution to journalArticle

Amstrup, Bjarne ; Lörincz, András ; Rice, Stuart A. / Population inversion in a multilevel system : A model study. In: Journal of Physical Chemistry. 1993 ; Vol. 97, No. 23. pp. 6175-6183.
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