Bifurcations as dissociation mechanism in bichromatically driven diatomic molecules

Abstract

We discuss the influence of periodic orbits on the dissociation of a model diatomic molecule driven by a strong bichromatic laser fields. Through the stability of periodic orbits, we analyze the dissociation probability when parameters, such as the two amplitudes and the phase lag between the laser fields, are varied. We find that qualitative features of dissociation can be reproduced by considering a small set of short periodic orbits. The good agreement with direct simulations demonstrates the importance of bifurcations of short periodic orbits in the dissociation dynamics of diatomic molecules.

Classical study of the rovibrational dynamics of a polar diatomic molecule in static electric fields

“…In particular, it has been demonstrated that the transition to chaos is connected with the overlapping of vibrational-rotational nonlinear resonances and appears at rather low radiation field intensities [29,30]. The dissociation dynamics of a diatomic molecule driven by a bichromatic field has been analyzed in terms of periodic bifurcations [31]. For polyatomic molecules, it has been demonstrated that classical stationary objects, e.g., equilibria, periodic orbits, tori or manifolds, act as organizing structures for the quantum mechanical eigenstates and their identification is needed for the spectral assignment of highly excited levels [32].…”

Role of the range of the dipole function in the classical dynamics of molecular dissociation

“…It should be noticed that for increasing frequency bandwidths and amplitudes of the external field, additional Fourier components have to be taken into account in the approximation made in Eq. (11).…”

“…When the oscillator is subjected to an external driving field, a particle in the bound region can escape to the unbound region and this transition corresponds to the dissociation of the molecule. The dissociation occurs through chaotic routes, * eflima@rc.unesp.br † tarciusnramos@gmail.com ‡ regydio@rc.unesp.br as a result of the destruction of Kolmogorov-Arnold-Moser (KAM) tori in phase-space for increasing values of the field amplitude [3,20].Several works have investigated the classical dissociation dynamics within the driven Morse model [1][2][3][4][5][6][7][8][9][10][11][12][21][22][23][24][25][26]. Also, many quantum-classical comparisons have been performed and correspondences between the two theories have been found in some situations [27][28][29][30][31][32][33][34][35][36][37].…”

“…In this context, it is shown that the suppression of dissociation of heteronuclear molecules for certain frequencies of the external field is a consequence of the finite range of the corresponding permanent dipole. The classical driven Morse oscillator has been extensively applied to the study of the dissociation dynamics of heterodiatomic molecules by means of infrared laser fields [1][2][3][4][5][6][7][8][9][10][11][12]. The interaction between the molecule and the laser field is commonly given by the product of a time-dependent external field, which accounts for the electric field of the laser, with a position-dependent function, associated with the permanent dipole moment of the molecule.…”

Driving the formation of the RbCs dimer by a laser pulse: A nonlinear-dynamics approach

“…Some examples of such as studies can be found in Refs. [23][24][25][26][27][28][29][30][31][32][33]. Furthermore, classical studies in microscopic systems have revealed themselves as a power tool to understand quantum mechanical results in many cases (see e.g.…”