Double-quantum two-dimensional electronic spectroscopy of a three-level system: Experiments and simulations

Research output: Contribution to journalArticle

Abstract

Double-quantum coherence two-dimensional (2Q2D) electronic spectroscopy is utilized to probe the dynamic fluctuations of electronic states in a solvated molecule at approximately twice the energy of the ground state bleach transition. The 2Q2D spectrum gives insight into the energetic position and spectral fluctuations (system-bath interaction) of the probed excited states. Combining it with single-quantum two-dimensional (1Q2D) electronic spectroscopy enables one to determine the strength of the excited state absorption transition and the relative detuning of electronic states, as well as the dynamics of the single-quantum coherence. To investigate the correlation of spectral fluctuations in different electronically excited states, we have carried out experiments on a solvated dye (Rhodamine 6G) with 23 fs pulses centered at the maximum of the linear absorption spectrum. The 2Q2D spectrum reveals three peaks of alternating signs with the major negative peak located at higher frequencies along the emission axis compared to the single positive peak. The 1Q2D spectrum, on the other hand, shows a negative peak stemming from excited state absorption at lower frequencies along the emission axis. Analysis of the signal in the homogeneous limit fails to account for this observation as well as the number of peaks in the 2Q2D spectrum. Employing a three-level model in which all time correlations of the third-order response function are accounted for via second-order cumulant expansion gives good agreement with both the 1Q2D and 2Q2D data. Furthermore, the analysis shows that the fluctuations of the probed electronic states are highly correlated, reflecting the modulation by a common nuclear bath and similarities in the nature of the electronic transitions. (C) 2010 American Institute of Physics. [doi: 10.1063/1.3474995]

Details

Authors
  • Alexandra Nemeth
  • Franz Milota
  • Tomas Mancal
  • Tönu Pullerits
  • Jaroslaw Sperling
  • Juergen Hauer
  • Harald F. Kauffmann
  • Niklas Christensson
Organisations
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Atom and Molecular Physics and Optics

Keywords

  • spectral line intensity, solvation, potential energy surfaces, ground states, dyes, excited states, spectral line shift, two-dimensional spectra
Original languageEnglish
JournalJournal of Chemical Physics
Volume133
Issue number9
Publication statusPublished - 2010
Publication categoryResearch
Peer-reviewedYes

Bibliographic note

The information about affiliations in this record was updated in December 2015. The record was previously connected to the following departments: Chemical Physics (S) (011001060)