Photon-momentum transfer in diatomic molecules: An ab initio study

Abstract

For a molecule, the two-center interference and the molecular scattering phase of the electron are important for almost all the processes that may occur in a laser field. In this study, we investigate their effects in the transfer of linear photon momentum to the ionized electron by absorbing a single photon. The time-dependent Schrödinger equation of H + 2 is numerically solved in the multipolar gauge in which the electric quadrupole term and the magnetic dipole term are explicitly expressed. This allows us to separate the contributions of the two terms in the momentum transfer. For different configurations of the molecular and the laser orientation, the transferred momentum to the electron is evaluated at different internuclear distances with various photon energies and two-center interferences are identified in the whole region. At small electron energies and small internuclear distances, we find significant deviations from the prediction of the classical double-slit model due to the strong mediation of the Coulomb potential. Finally, even for a large internuclear distance, our results show that a varying molecular scattering phase is important at all electron energies, which is beyond the simple prediction of the linear combination of the atomical orbitals.

Photon Momentum Transfer in Single-Photon Double Ionization of Helium

“…It is worth pointing out that Eqs. (7) and (8) are quite similar to the known relation in the one-photon single ionization of hydrogen [2],…”

“…For the hydrogen atom in different initial states, Seaton [5] theoretically investigated the momentum sharing, pointing out that momentum transfer is important in astrophysics. In more recent works, the problem of photon momentum sharing has been extended from atoms to molecules [6,7] and to the nonsequential double ionization of atoms in the tunneling regime [8].…”

“…The Hamiltonian in the LG and the VG, respectively, is given by [7,28,29] (atomic units are used throughout this Letter unless otherwise stated),…”

Nondipole effects in interference patterns of a two-electron wave

“…Specific forms of each term in the Hamiltonian can be found in Refs. [13] and [14]. It is worth to mention that, unlike the atomic case [15], the last term in Eq.…”

Laser-induced electron Fresnel diffraction by XUV pulses at extreme intensity

“…While the works mentioned above were carried out within the dipole approximation, strong-field physics beyond that approximation has attracted increasingly more interest in recent years [16]. It has been shown both experimentally and theoretically that nondipole corrections to the Hamiltonian can induce a photon-momentum transfer to the photoelectron [17][18][19][20][21][22][23]. Besides, when atoms are exposed to the extreme ultraviolet (XUV) pulse of high intensity, the nondipole corrections can alter the dynamic interference [24].…”