Carrier-Envelope-Phase Effects in Ultrafast Strong-Field Ionization Dynamics of Multielectron Systems: Xe andCS2

Abstract

Carrier-envelope-phase- (CEP) stabilized 5 and 22 fs pulses of intense 800 nm light are used to probe the strong-field ionization dynamics of xenon and carbon disulfide. We compare ion yields obtained with and without CEP stabilization. With 8-cycle (22 fs) pulses, Xe(6+) yields are suppressed (relative to Xe(+)) by 30%-50%, depending on phase, reflecting the phase dependence of nonsequential ionization and its contribution to the formation of higher charge states. Ion yields for Xe(q+) (q = 2-4) with CEP-stabilized pulses are enhanced (by up to 50%) compared to those with CEP-unstabilized pulses. Such enhancement is particularly pronounced with 2-cycle (5 fs) pulses and is distinctly phase dependent. Orbital shape and symmetry affect how CS(2) responds to variations in optical field that are effected as CEP is altered, keeping intensity constant. Molecular fragmentation is found to depend on field strength (not intensity); the relative enhancement of fragmentation when CEP-stabilized 2-cycle pulses are used is found to be at the expense of molecular ionization.

Using the carrier-envelope phase to control strong-field dissociation of HeH+ at midinfrared wavelengths

“…Similar studies on CO have predicted that two-color pulses can be used to control molecular orientation [4,12,13]. These theoretical predictions have been realized in experiments starting from the neutral targets H 2 [14][15][16][17][18], D 2 [13,15,[18][19][20][21][22], HD [19,23], CO [4,13,[24][25][26], DCl [27,28], and small polyatomic molecules [29][30][31][32][33][34][35][36][37]. More recently, experimental CEP control has been demonstrated directly on H + 2 [38][39][40].…”

Strong-field control of the dissociative ionization of N2O with near-single-cycle pulses

“…They found that laser-driven recollisional ionization and excitation caused a π-periodic oscillation of the ionization and fragmentation yields with CEP. Mathur et al studied the strong-field dissociative ionization dynamics of CS 2 molecules and found CEP-dependent modulations in the fragmentation yields [44]. Processes depending on the direction of the electric field have also been predicted for larger molecules (see e.g.…”

Phase- and intensity-dependence of ultrafast dynamics in hydrocarbon molecules in few-cycle laser fields

“…[30][31][32][33][34][35]). CEP effects in the deprotonation of acetylene, induced by few-cycle laser pulses, have attracted considerable interest.…”