TY  - JOUR
A1  - Paramonov, Guennaddi K.
A1  - Kühn, Oliver
A1  - Bandrauk, André D.
T1  - Excitation of H+ 2 with one-cycle laser pulses
BT  - shaped post-laser-field electronic oscillations, generation of higher- and lower-order harmonics
JF  - Molecular physics : MP ; an international journal in the field of chemical physics
N2  - Non-Born–Oppenheimer quantum dynamics of H+ 2 excited by shaped one-cycle laser pulses linearly polarised along the molecular axis have been studied by the numerical solution of the time-dependent Schrödinger equation within a three-dimensional model, including the internuclear separation, R, and the electron coordinates z and ρ. Laser carrier frequencies corresponding to the wavelengths λ l = 25 nm through λ l = 400 nm were used and the amplitudes of the pulses were chosen such that the energy of H+ 2 was close to its dissociation threshold at the end of any laser pulse applied. It is shown that there exists a characteristic oscillation frequency ωosc ≃ 0.2265 au (corresponding to the period of τosc ≃ 0.671 fs and the wavelength of λosc ≃ 201 nm) that manifests itself as a ‘carrier’ frequency of temporally shaped oscillations of the time-dependent expectation values ⟨z ⟩ and ⟨∂V/∂z ⟩ that emerge at the ends of the laser pulses and exist on a timescale of at least 50 fs. Time-dependent expectation values ⟨ρ⟩ and ⟨∂V /∂ρ⟩ of the optically passive degree of freedom, ρ, demonstrate post-laser-field oscillations at two basic frequencies ωρ 1 ≈ ωosc and ωρ 2 ≈ 2ωosc. Power spectra associated with the electronic motion show higher- and lower-order harmonics with respect to the driving field.
KW  - One-cycle laser pulses
KW  - post-laser-field electronic oscillations
KW  - generation of higher and lower harmonics
Y1  - 2017
U6  - https://doi.org/10.1080/00268976.2017.1288938
SN  - 0026-8976
SN  - 1362-3028
VL  - 115
IS  - 15/16
SP  - 1846
EP  - 1860
PB  - Taylor & Francis
CY  - London
ER  -