Real-time dynamics of Auger wave packets and decays in ultrafast charge migration processes

  title={Real-time dynamics of Auger wave packets and decays in ultrafast charge migration processes},
  author={Fabio Covito and Enrico Perfetto and {\'A}ngel Rubio and Gianluca Stefanucci},
  journal={Physical Review A},
The Auger decay is a relevant recombination channel during the first few femtoseconds of molecular targets impinged by attosecond XUV or soft x-ray pulses. Including this mechanism in time-dependent simulations of charge-migration processes is a difficult task, and Auger scatterings are often ignored altogether. In this work we present an advance of the current state-of-the-art by putting forward a real-time approach based on nonequilibrium Green's functions suitable for first-principles… 

Figures from this paper

First-principles nonequilibrium Green's function approach to ultrafast charge migration in glycine.

This work investigates the photo-induced ultrafast charge migration phenomenon in the glycine molecule using a recently proposed nonequilibrium Green's functions (NEGF) approach and shows that electronic correlations renormalize the bare frequencies, redistribute the spectral weights and give rise to new spectral features.

Time-Stretched Spectroscopy by the Quantum Zeno Effect: The Case of Auger Decay.

This work exemplifies their approach with the Auger process, and finds that repeated measurements increase the core-hole lifetime, redistribute the kinetic energy of Auger electrons, and alter entanglement formation.

Modeling ultrafast out-of-equilibrium carrier dynamics and relaxation processes upon irradiation of hexagonal silicon carbide with femtosecond laser pulses

We present a theoretical investigation of the yet unexplored dynamics of the produced excited carriers upon irradiation of hexagonal Silicon Carbide (6H-SiC) with femtosecond laser pulses. To

Real-time observation of a correlation-driven sub 3 fs charge migration in ionised adenine

Sudden ionisation of a relatively large molecule can initiate a correlation-driven process dubbed charge migration, where the electron density distribution is expected to rapidly move along the

CHEERS: a tool for correlated hole-electron evolution from real-time simulations

CHEERS is a computational tool to solve the NEGF equation of motion in the so called generalized Kadanoff-Baym ansatz and it can be used for model systems as well as first-principles Hamiltonians.

Benchmarking nonequilibrium Green’s functions against configuration interaction for time-dependent Auger decay processes

Abstract We have recently proposed a nonequilibrium Green’s function (NEGF) approach to include Auger decay processes in the ultrafast charge dynamics of photoionized molecules. Within the so-called

Ultrafast dynamics of adenine following XUV ionization

The dynamics of biologically relevant molecules exposed to ionizing radiation contains many facets and spans several orders of magnitude in time and energy. In the extreme ultraviolet (XUV) spectral

Ultrafast dynamics of strongly correlated fermions—nonequilibrium Green functions and selfenergy approximations

A selfcontained introduction to the theory of NEGF is presented and an overview on recent numerical applications to compute the ultrafast relaxation dynamics of correlated fermions is given.

Time‐dependent simulation of ion stopping: Charge transfer and electronic excitations

The energy loss of charged particles in matter has been studied for many decades, both, analytically and via computer simulations. While the regime of high projectile energies is well understood, low

Accelerating Nonequilibrium Green functions simulations with embedding selfenergies

Real-time nonequilibrium Green functions (NEGF) have been very successful to simulate the dynamics of correlated many-particle systems far from equilibrium. However, NEGF simulations are



Theory of laser-assisted Auger processes generated by ultrashort XUV pulses in atoms

A non-stationary quantum mechanical theory of the laser-assisted Auger process in atoms excited by an ultrashort (attosecond) electromagnetic pulse in the field of a few-cycle strong optical laser

Attosecond real-time observation of electron tunnelling in atoms

The real-time observation of this most elementary step in strong-field interactions: light-induced electron tunnelling is reported, and the process is found to deplete atomic bound states in sharp steps lasting several hundred attoseconds, suggesting a new technique, attose Cond Tunnelling, for probing short-lived, transient states of atoms or molecules with high temporal resolution.

Time-dependent theory of Auger decay induced by ultra-short pulses in a strong laser field

A quantum mechanical theory of a laser-assisted Auger process in atoms excited by an ultra-short (attosecond) electromagnetic pulse in the field of a few-cycle strong laser pulse is presented. It is

Attosecond imaging of XUV-induced atomic photoemission and Auger decay in strong laser fields

Velocity-map imaging has been employed to study the photoemission in Ne and N4,5OO Auger decay in Xe induced by an isolated 85 eV extreme ultraviolet (XUV) pulse in the presence of a strong few-cycle

Time-resolved atomic inner-shell spectroscopy

It is demonstrated that a laser-based sampling system, consisting of a few-femtosecond visible light pulse and a synchronized sub-feminine soft X-ray pulse, allows us to trace the relaxation dynamics of core-excited atoms directly in the time domain with attosecond resolution.

Ultrafast correlation-driven electron dynamics

Exposing molecules to ultrashort laser pulses creates electronic wave packets, and therefore, triggers pure electron dynamics in the excited or ionized system. In the case of ionization, these

Quantum coherence in the time-resolved Auger measurement.

The transition from a quasiclassical energy shift of the spectrum to the formation of sidebands and the enhancement of high- and low-energy tails of the Auger spectrum due to quantum coherence between photoionization and Auger decay is explained.

First-principles nonequilibrium Green's-function approach to transient photoabsorption: Application to atoms

We put forward a first-principle nonequilibrium Green’s-function (NEGF) approach to calculate the transient photoabsorption spectrum of optically thin systems. The method can deal with pump fields of

Control of charge migration in molecules by ultrashort laser pulses

Due to electronic many-body effects, the ionization of a molecule can trigger ultrafast electron dynamics appearing as a migration of the created hole charge throughout the system. Here we propose a

Ultrafast Charge Migration in XUV Photoexcited Phenylalanine: A First-Principles Study Based on Real-Time Nonequilibrium Green's Functions.

The results show that dynamical correlations are necessary for a quantitative overall agreement with the experimental data and a first-principles nonequilibrium Green's function method fulfilling all three requirements is proposed and applied to a recent experiment on the photoexcited phenylalanine amino acid.