Share Email Print

Proceedings Paper

Theory of non-Condon femtosecond quantum beats in electronic transitions of dye molecules
Author(s): Yuri T. Mazurenko; Vadim V. Smirnov
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

Recently experiments have been conducted in which the femtosecond oscillations of light absorption by dye molecules were observed. These oscillations were induced when the molecules were excited by femtosecond light pulses. It was shown that the oscillation frequencies correspond well to those of molecular vibrations. For this reason the oscillations observed were explained as the result of quantum beats of vibrational molecular states.1'2 As is already known the quantum beats can occur when several, at least two closely spaced quantum levels are excited simultaneously. Such excitation should be performed by a pulse which is shorter than the period of oscillations corresponding to the energetic distance between two levels. Then interference of the stationary wave functions occurs. If the probabilities of optical transitions from the levels considered to some third level are different the the interference of stationary states leads to the modulation of absorption or emission intensity. The vibrational quantum beats can exist when the coherent superposition of several stationary vibrational states is created. This actually means the oscillation in phase of a number of molecules, which can be observed in the absorption or emission of light. In this paper we should like to draw attention to the essential significance of whether the observation of vibrational quantum beats is carried out with spectral selectivity or without it.

Paper Details

Date Published: 1 May 1991
PDF: 4 pages
Proc. SPIE 1403, Laser Applications in Life Sciences, (1 May 1991); doi: 10.1117/12.57284
Show Author Affiliations
Yuri T. Mazurenko, S. I. Vavilov State Optical Institute (Russia)
Vadim V. Smirnov, S. I. Vavilov State Optical Institute (Russia)

Published in SPIE Proceedings Vol. 1403:
Laser Applications in Life Sciences
Sergei A. Akhmanov; Marina Yu. Poroshina, Editor(s)

© SPIE. Terms of Use
Back to Top