Abstract
We examine computationally how ultrashort polarized strong one cycle IR pulses can be used for steering coherent nuclear dynamics in LiH. The nuclear motion is described using the time-dependent Schrödinger equation on a grid for several coupled electronic states. The coupling to the strong field of the pump and probe pulses is included in the Hamiltonian as well as the non adiabatic coupling between the different electronic states. LiH possesses low lying Σ and Π states that can be selectively accessed by controlling the polarization of the pump pulse along the bond or perpendicularly to it. In addition, when using a one cycle pulse, controlling the carrier envelope phase (CEP) allows to select the states that will be coherently excited according to their polarity. Since some of the excited Σ states and all the Π states are repulsive, polarization and CEP control of the pump pulse leads to controlling the dissociation yields. In particular, our quantum dynamics simulations show that the ratio of the fragmentation yields of the Σ2 and Σ3 states can be changed by a factor 10 when the CEP of a one cycle IR pulse polarized along the bond is switched from 0 to π. In addition to probing the dynamics by following the fragmentation, we also report on probing the coherent vibronic wave packet using transient absorption spectra that results from the interaction of the molecular transition dipole with the electric fields of the pump and the probe pulses. The emission spectrum retrieves the different time scales of the vibronic dynamics and probes the time evolution of the coherences.
Original language | English |
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Title of host publication | Springer Series in Chemical Physics |
Publisher | Springer New York LLC |
Pages | 41-65 |
Number of pages | 25 |
Edition | 9783319648392 |
DOIs | |
State | Published - 2017 |
Publication series
Name | Springer Series in Chemical Physics |
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Number | 9783319648392 |
ISSN (Print) | 0172-6218 |
Bibliographical note
Publisher Copyright:© Springer International Publishing AG 2017.