Quantum-classical modeling of nonlinear pulse propagation in a dissolved two-photon active chromophore.
In the present work we outline the implications of a quantum-classical approach for modeling two-photon absorption of organic chromophores in solution. The approach joins many-photon absorption dynamic simulations with quantum chemical first principles calculations of corresponding excitation energies and transition matrix elements. Among a number of conclusions of the study, we highlight three: (i) The use of either short- or long-pulse excitation is demonstrated to switch the absorptive capacity of the nonlinear medium owing to enhancement of the nonlinear stepwise processes; (ii) The two-photon cross section strongly depends on the way in which the dephasing rate decays when the laser frequency is tuned off-resonant with the corresponding molecular transition; (iii) The results of the pulse propagation simulations based on electronic structure data obtained with a new Coulomb attenuated functional is shown to be in much better agreement with the experimental results than those based on data received with traditional density functionals.
Baev
Alexander
A
Institute for Lasers, Photonics and Biophotonics, State University of New York at Buffalo, New York 14260-3000, USA. abaev@buffalo.edu
Salek
Pawel
P
Gel'mukhanov
Faris
F
Agren
Hans
H
D000042:Absorption; D000465:Algorithms; D004583:Electrons; D005449:Fluorenes / Q000737:chemistry*; D017711:Nonlinear Dynamics; D017785:Photons; D011789:Quantum Theory
D005449:Fluorenes