Classical-trajectory simulation of accelerating neutral atoms with polarized intense laser pulses

Abstract

In the present paper, we perform the classical trajectory Monte Carlo simulation of the complex dynamics of accelerating neutral atoms with linearly or circularly polarized intense laser pulses. Our simulations involve the ion motion as well as the tunneling ionization and the scattering dynamics of valence electron in the combined Coulomb and electromagnetic fields, for both helium (He) and magnesium (Mg). We show that for He atoms, only linearly polarized lasers can effectively accelerate the atoms, while for Mg atoms, we find that both linearly and circularly polarized lasers can successively accelerate the atoms. The underlying mechanism is discussed and the subcycle dynamics of accelerating trajectories is investigated. We have compared our theoretical results with a recent experiment [Eichmann Nature (London) 461, 1261 (2009)].

Theoretical Study of Isolated Attosecond Pulse Generation with Two Methods

“…For the case of ϕ = 0.5π, a smooth structure is obtained near the cut off area, and the cut off of the HHG extend to 205 eV, but the intensity is lower than the case of ϕ = 0. One of the difference with our previous work [13] is that the cut off extend for the case of ϕ = 0.5π, but the result shown in Ref. [13] (Fig.…”

“…One of the difference with our previous work [13] is that the cut off extend for the case of ϕ = 0.5π, but the result shown in Ref. [13] (Fig. 2) is for the case of the wavelength equal 800 nm for the two circular pulses.…”

“…The DOG scheme can be obtained by adding another pulse to a PG scheme, this means that the frequency of the two circularly polarized laser pulse is equal . In our previous work [13], we investigated the IAP generation by two circularly polarized pulses with different frequencies, and found that the quantum paths can be controlled. In this paper, we theoretically study the IAP by combining a left circularly polarized pulse with a right circular polarized pulse, and the frequencies are different for the two pulses.…”

Generation of an isolated few-attosecond pulse in optimized inhomogeneous two-color fields

“…It is well known that generation of isolated attosecond pulses is a manifestation of phase matching of just one-type of (i.e. either long or short, but not both) quantum paths in the supercontinuum regime [16,17]. Simultaneous superposition of both long and short quantum paths can destructively interfere with each other…”

Excitation and Ionization of Xenon Atoms in Strong UV Laser Fields

“…Recently, it is surprised to find that, both theoretically [4] and experimentally [5], neutral atoms can survive strong laser fields in Rydberg states, known as Rydberg state excitation (RSE). Moreover, recent investigations have demonstrated that the RSE is closely connected to some interesting phenomena such as the absence of near-zeromomentum electrons [6] and the acceleration of neutral Rydberg atoms [7,8], and is also very useful in the enhancement of HHG [9]. Elaborate experimental and theoretical studies have been performed on this new strong-field phenomenon in the past few years [10][11][12][13].…”