Probing Molecular Frame Wigner Time Delay and Electron Wavepacket Phase Structure of CO Molecule

Abstract

The time delay of photoelectron emission serves as a fundamental building block to understand the ultrafast electron emission dynamics in strong-field physics. Here, we study the photoelectron angular streaking of CO molecules by using two-color (400+800 nm) corotating circularly polarized fields. By coincidently measuring photoelectrons with the dissociative ions, we present molecular frame photoelectron angular distributions with respect to the instantaneous driving electric field signatures. We develop a semiclassical nonadiabatic molecular quantum-trajectory Monte Carlo (MO-QTMC) model that fully captures the experimental observations and further ab initio simulations. We disentangle the orientation-resolved contribution of the anisotropic ionic potential and the molecular orbital structure on the measured photoelectron angular distributions. Furthermore, by analyzing the photoelectron interference patterns, we extract the sub-Coulomb-barrier phase distribution of the photoelectron wavepacket and reconstruct the orientation- and energy-resolved Wigner time delay in the molecular frame. Holographic angular streaking with bicircular fields can be used for probing polyatomic molecules in the future.

Highly Sensitive Hydrogen Sensing Based on Tunable Diode Laser Absorption Spectroscopy with a 2.1 μm Diode Laser

“…This optimum modulation depth was kept for use in the subsequent experiments. In addition, the small value of the optimal modulation depth also proves that H 2 has a narrow absorption line width compared to other gases [51][52][53][54][55][56][57]. In order to evaluate the response performance of the WMS-HMPC-based H 2 -TDLAS sensing system, H 2 with a concentration of 100% and pure nitrogen (N 2 ) were sent into the gas dilution system, respectively, and mixed gases with H 2 concentrations of 100%, 80%, 60%, 40%, 20%, 10%, and 5% were obtained by controlling the flow rate of two gas flowmeters in the dilution system.…”

Controlling Magnetic and Electric Nondipole Effects with Synthesized Two Perpendicularly Propagating Laser Fields

“…Such controlling scenario should attracted much attention in ultrafast and strongfield physics, and this would have a promising perspective on controlling nondipole effects for more molecules with bi-circular fields. [48,49]…”

Sensitive carbon monoxide detection based on laser absorption spectroscopy with hollow‐core antiresonant fiber

“…[20][21][22][23][24][25] It has the merits of high sensitivity and high selectivity. [26][27][28][29][30][31][32][33] Among them, tunable diode laser absorption spectroscopy (TDLAS) technology is extensively used in various types of gas detection and offers many advantages such as high sensitivity, low cost, quick response time and noncontact measurement. 34,35 In TDLAS, a photodetector is used to gauge the change in intensity of light.…”

“…Laser absorption spectroscopy based methods are extensively used for trace gas detection 20–25 . It has the merits of high sensitivity and high selectivity 26–33 . Among them, tunable diode laser absorption spectroscopy (TDLAS) technology is extensively used in various types of gas detection and offers many advantages such as high sensitivity, low cost, quick response time and noncontact measurement 34,35 .…”