Correlated electron-nuclear dynamics in above-threshold multiphoton ionization of asymmetric molecule

Abstract

The partition of the photon energy into the subsystems of molecules determines many photon-induced chemical and physical dynamics in laser-molecule interactions. The electron-nuclear energy sharing from multiphoton ionization of molecules has been used to uncover the correlated dynamics of the electron and fragments. However, most previous studies focus on symmetric molecules. Here we study the electron-nuclear energy sharing in strong-field photoionization of HeH2+ by solving the one-dimensional time-dependent Schrödinger equation (TDSE). Compared with symmetric molecules, the joint electron-nuclear energy spectrum (JES) of HeH2+ reveals an anomalous energy shift at certain nuclear energies, while it disappears at higher and lower nuclear energies. Through tracing the time evolution of the wavepacket of bound states, we identify that this energy shift originates from the joint effect of the Stark shift, associated with the permanent dipole, and the Autler-Townes effect due to the coupling of the 2pσ and 2sσ states in strong fields. The energy shift in the JES appears at certain nuclear distances only when both Stark effect and Autler-Townes effect play important roles. We further demonstrate that the electron-nuclei energy sharing can be controlled by varying laser intensity for asymmetric molecules, providing alternative approaches to manipulate photochemical reactions for more complex molecules.

Universal time delay in the recollision impact ionization pathway of strong-field nonsequential double ionization

“…The particular interest in NSDI is the highly correlated behavior of the ionized electron pairs [3]. During the past three decades, a great number of experimental and theoretical studies have been performed on NSDI [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22] and the underlying electron dynamics has been well explored. Generally, the mechanism of NSDI can be understood by the rescattering picture [23,24], where the outermost electron firstly tunnels through the distorted potential barrier formed by the atomic potential and the intense laser field, and then the freed electron is accelerated by the oscillating field and impelled back to recollide with the parent ion inelastically after the electric field changes sign, leading to the ionization of the second electron.…”

Heteronuclear Limit of Strong-Field Ionization: Fragmentation of HeH+ by Intense Ultrashort Laser Pulses

“…On the theory side, the solution of the time-dependent Schrödinger equation (TDSE) with all 9 degrees of freedom necessary to describe HeH + is extremely challenging and unfeasible with current computational resources. Therefore, approximations such as TDSE calculations with reduced dimensionality [12][13][14] or semiclassical approaches [15] are often used.…”

Progress of ultrafast dissociation dynamics for the hydrogen molecule ions

“…在随后的研究中 [54,55] 少周期效应的"垂直条纹" [56] 及违反直觉的能量移动 [57] 等. 2017年, Wang等人 [58] Figure 7 (Color online) The converged two dimensional nuclear momentum distributions when the time delay between the attosecond and mid-infrared (MIR) pulses is Δt=−0.3 T (a) and Δt=−0.66 T (b). T refers to the period of MIR laser.…”