# Dresden 2017 – wissenschaftliches Programm

## Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

# DF: Fachverband Dielektrische Festkörper

## DF 8: Ferroics - Domains, Domain Walls and Skyrmions I

### DF 8.2: Vortrag

### Dienstag, 21. März 2017, 10:00–10:15, WIL B321

**Universal relations between electromagnetic response functions: towards a first-principles description of magneto-electric materials** — •Giulio Schober^{1} and Ronald Starke^{2} — ^{1}Institute for Theoretical Physics, Heidelberg University, Philosophenweg 19, 69120 Heidelberg, Germany — ^{2}Institut für Theoretische Physik, TU Bergakademie Freiberg, Leipziger Str. 23, 09596 Freiberg

Based on modern microscopic approaches to electrodynamics of materials, we systematically investigate the mutual functional dependencies of induced, external and total electromagnetic field quantities. This allows for a unified, relativistic description of the electromagnetic response without assuming the material to be composed of electric or magnetic dipoles. Using this approach, we derive universal (material-independent) relations between electromagnetic response functions such as the dielectric tensor, the magnetic susceptibility and the microscopic conductivity tensor. Our formulae can be reduced to well-known identities in special cases, but more generally include the effects of inhomogeneity, anisotropy, magneto-electric cross-coupling and relativistic retardation. If combined with the Kubo formalism, they would therefore lend themselves to the ab initio calculation of all linear electromagnetic response functions, thus paving the way for a first-principles description of magneto-electric materials for spintronics applications.