Attosecond Time Delays in Photodetachment of Nitrate Anion
Oral
Abstract
Measuring attosecond time delays provides information about the wave-function phase in photoionization
processes, thus providing insight into the electronic dynamics and structure of atomic and molecular systems.
In contrast to the photoionization of neutral species that have been extensively studied in the last decade,
photodetachment of negative ions has received much less attention, especially experimentally due to challenges
in preparing the anions. Since the outgoing photoelectron interacts
with a neutral species after the detachment, the absence of the long-range Coulomb potential allows easier observation
of correlation and polarization effects.
To stimulate experimental efforts in photodetachment time delay measurements, we conducted ab initio theoretical studies
of valence and core photodetachment of nitrate anion (NO3-). In both cases, the nitrate anion exhibits
several shape resonances at low photoelectron energies below 20 eV with time delays up to 600 attoseconds.
In this contribution, we will present our simulations of the
RABITT (Reconstruction of Attosecond Beating by Two-photon Transitions) and Streaking experiments
in molecular and laboratory frames using the R-matrix method. We will discuss the effect of the additional IR
field on the direct measurement of the one-photon (Wigner) delay that is directly related to the detachment dynamics
induced by the high-frequency field.
processes, thus providing insight into the electronic dynamics and structure of atomic and molecular systems.
In contrast to the photoionization of neutral species that have been extensively studied in the last decade,
photodetachment of negative ions has received much less attention, especially experimentally due to challenges
in preparing the anions. Since the outgoing photoelectron interacts
with a neutral species after the detachment, the absence of the long-range Coulomb potential allows easier observation
of correlation and polarization effects.
To stimulate experimental efforts in photodetachment time delay measurements, we conducted ab initio theoretical studies
of valence and core photodetachment of nitrate anion (NO3-). In both cases, the nitrate anion exhibits
several shape resonances at low photoelectron energies below 20 eV with time delays up to 600 attoseconds.
In this contribution, we will present our simulations of the
RABITT (Reconstruction of Attosecond Beating by Two-photon Transitions) and Streaking experiments
in molecular and laboratory frames using the R-matrix method. We will discuss the effect of the additional IR
field on the direct measurement of the one-photon (Wigner) delay that is directly related to the detachment dynamics
induced by the high-frequency field.
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Presenters
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Jan Dvorak
- University of Central Florida