Laser control of the radiationless decay in pyrazine using the dynamic Stark effect.
The laser control of the radiationless decay between the B(3u)(nπ*) and B(2u)(ππ*) states of pyrazine using the dynamic Stark effect has been investigated. A vibronic coupling model Hamiltonian in diabatic representation, including potential energy, transition dipole, and static polarizability surfaces as a function of the four most important vibrational modes of the molecule has been parametrized using multi-reference electronic structure calculations. The interaction of the molecule with a strong non-resonant laser pulse has been analyzed in terms of dressed potential energy surfaces. Because of the large polarizability difference between the vibronically coupled B(3u)(nπ*) and B(2u)(ππ*) states, the Stark effect induced by the non-resonant laser pulse shifts the conical intersection away from the Franck-Condon region. We have shown, by solving the time-dependent Schrödinger equation for the molecule interacting with a relatively weak pump pulse driving the electronic excitation from the ground state to the B(2u)(ππ*) state, and a strong non-resonant control pulse, that this control mechanism can be used to trap the wavepacket on the B(2u)(ππ*) potential energy surface for a much longer time than the natural B(2u)(ππ*) lifetime.
Laboratoire Interdisciplinaire Carnot de Bourgogne UMR 6303 CNRS, Université de Bourgogne, BP 47870, F-21078 Dijon, France.
Matthieu
M
Sala
CTMM, Institut Charles Gerhardt UMR 5253 CNRS, CC 15001, Université Montpellier 2, F-34095 Montpellier, France.
Mohamad
M
Saab
CTMM, Institut Charles Gerhardt UMR 5253 CNRS, CC 15001, Université Montpellier 2, F-34095 Montpellier, France.
Benjamin
B
Lasorne
CTMM, Institut Charles Gerhardt UMR 5253 CNRS, CC 15001, Université Montpellier 2, F-34095 Montpellier, France.
Fabien
F
Gatti
Laboratoire Interdisciplinaire Carnot de Bourgogne UMR 6303 CNRS, Université de Bourgogne, BP 47870, F-21078 Dijon, France.
Stéphane
S
Guérin