TITLE: Challenges in Theoretical Spectroscopy
AUTHOR: Claudia Draxl- Physics Department and CSMB, Humboldt-Universität zu Berlin, Berlin, Germany @email
INVITED BY: Antonio Picón
WHEN: April, 8 - 12PM (coffee at 11.30AM)
WHERE: Salón de Actos, ICMM - Calle Sor Juana Inés de la Cruz, 3 - Campus de Cantoblanco, Madrid
ABSTRACT: Many-body approaches to electronic excitations have become an indispensable tool for an in-depth understanding of the subtle processes that take place in a wide variety of materials. In particular, many-body perturbation theory (MBPT) allows us to treat the interplay between competing interactions of similar strength and on the same energy scale, which can give rise to exciting phenomena. Elucidating the underlying mechanisms and keeping up with the recent developments in experimental techniques, requires the development of advanced methodologies. In this talk, I will first give an overview of the state-of-the-art methods in describing the response of matter to light on different length scales. Selected examples of optical absorption, core-level spectroscopy, and resonant inelastic x-rays scattering (RIXS) will highlight the interplay of electron-electron interaction, electron-vibrational coupling, electron-hole correlation, and exciton-exciton coupling. I will then report on our recent progress in developing methods to tackle exciton-phonon coupling and exciton dynamics, and discuss ways to keep such calculations within affordable computational times, even for complex materials.
