Sur ce site

Sur le Web du CNRS

Accueil du site > Séminaires > Séminaires 2014 > Time-resolved spectroscopies with time-dependent density-functional theory

Mardi 3 juin 2014-14:00

Time-resolved spectroscopies with time-dependent density-functional theory

Umberto De Giovannini (Nano-bio Spectroscopy Group, San Sebastian)

par Gabriel LeMarié - 3 juin 2014

Molecular absorption and photo-electron spectra can be efficiently predicted with real-time time-dependent density-functional theory (TDDFT) [1]. We show how these techniques can be easily extended to study time-resolved pump-probe experiments in which a system response (absorption or electron emission) to a probe pulse, is measured in an excited state [2]. This simulation tool helps to interpret the fast evolving attosecond time-resolved spectroscopic ex- periments, where the electronic motion must be followed at its natural time-scale. We show how the extra degrees of freedom (pump pulse duration, intensity, frequency, and time-delay), which are absent in a conventional steady state experiment, provide additional information about electronic structure and dynamics that improve a system characterization. The theory is illustrated trough a set of test cases ranging from atomic to molecular systems selectively including the effects of vibrations in the ionic degrees of freedom [3].

PDF - 615.2 ko

[1] U. De Giovannini, D. Varsano, M. A. L. Marques, H. Appel, E. K. U. Gross, and A. Rubio, Phys. Rev. A 85, 062515 (2012).

[2] U. De Giovannini, G. Brunetto, A. Castro, J. Walkenhorst, and A. Rubio, Chemphyschem 14, 1363 (2013).

[3] A. Crawford Uranga, U. De Giovannini, D. J. Mowbray, S. Kurth, and A. Rubio, J. Phys. B (in press – .

Post-scriptum :

contact : P. Romaniello