We describe a first-principles NonEquilibrium Green's Function (NEGF) approach to time-resolved photoabsortion spectroscopy in atomic and nanoscale systems. The method is used to highlight a recently discovered dynamical correlation effect in the spectrum of a Krypton gas subject to a strong ionizing pump pulse. We propose a minimal model that captures the effect, and study the performance of time-local approximations versus time-nonlocal ones. In particular we implement the time-local Hartree-Fock and Markovian second Born (2B) approximation as well as the exact adiabatic approximation within the Time-Dependent Density Functional Theory framework. For the time-nonlocal approximation we instead use the 2B one. We provide enough convincing evidence for the fact that a proper description of the spectrum of an evolving admixture of ionizing atoms requires the simultaneous occurrence of correlation and memory effects.

Perfetto, E., Uimonen, A., Van Leeuwen, R., Stefanucci, G. (2016). Time-resolved photoabsorption in finite systems: A first-principles NEGF approach. JOURNAL OF PHYSICS. CONFERENCE SERIES, 696(1), 012004 [10.1088/1742-6596/696/1/012004].

Time-resolved photoabsorption in finite systems: A first-principles NEGF approach

Perfetto, E;STEFANUCCI, GIANLUCA
2016-01-01

Abstract

We describe a first-principles NonEquilibrium Green's Function (NEGF) approach to time-resolved photoabsortion spectroscopy in atomic and nanoscale systems. The method is used to highlight a recently discovered dynamical correlation effect in the spectrum of a Krypton gas subject to a strong ionizing pump pulse. We propose a minimal model that captures the effect, and study the performance of time-local approximations versus time-nonlocal ones. In particular we implement the time-local Hartree-Fock and Markovian second Born (2B) approximation as well as the exact adiabatic approximation within the Time-Dependent Density Functional Theory framework. For the time-nonlocal approximation we instead use the 2B one. We provide enough convincing evidence for the fact that a proper description of the spectrum of an evolving admixture of ionizing atoms requires the simultaneous occurrence of correlation and memory effects.
2016
Pubblicato
Rilevanza internazionale
Articolo
Sì, ma tipo non specificato
Settore FIS/03 - FISICA DELLA MATERIA
English
Physics and Astronomy (all)
http://www.iop.org/EJ/journal/conf
Perfetto, E., Uimonen, A., Van Leeuwen, R., Stefanucci, G. (2016). Time-resolved photoabsorption in finite systems: A first-principles NEGF approach. JOURNAL OF PHYSICS. CONFERENCE SERIES, 696(1), 012004 [10.1088/1742-6596/696/1/012004].
Perfetto, E; Uimonen, A; Van Leeuwen, R; Stefanucci, G
Articolo su rivista
File in questo prodotto:
File Dimensione Formato  
TPA_proceedings_resubmitted.pdf

solo utenti autorizzati

Licenza: Non specificato
Dimensione 524.68 kB
Formato Adobe PDF
524.68 kB Adobe PDF   Visualizza/Apri   Richiedi una copia

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2108/174006
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 9
  • ???jsp.display-item.citation.isi??? 8
social impact