Nonlinear spectrum effect on the coherent control of molecular systems

This work demonstrates that the detuning of the fs-laser spectrum from the two-photon absorption band of organic materials can be used to reach further control of the two-photon absorption by pulse spectral phase manipulation. We investigate the coherent control of the two-photon absorption in imidazole-thiophene core compounds presenting distinct two-photon absorption spectra. The coherent control, performed using pulse phase shaping and genetic algorithm, exhibited different growth rates for each sample. Such distinct trends were explained by calculating the two-photon absorption probability considering the intrapulse interference mechanism, taking into account the two-photon absorption spectrum of the samples. Our results indicate that tuning the relative position between the nonlinear absorption and the pulse spectrum can be used as a novel strategy to optimize the two-photon absorption in broadband molecular systems. (C) 2011 Elsevier B.V. All rights reserved.

FAPESP, Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

CNPq, Brazil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

CAPES, Brazil

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

U.S. Air Force Office of Scientific Research (AFOSR)

AFOSR, USA[FA9550-07-1-0374]

NSF[NSF HRD-0630456]

U.S. National Science Foundation (NSF)