Regensburg 2019 – wissenschaftliches Programm

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

HL: Fachverband Halbleiterphysik

HL 46: Ultra-fast phenomena

HL 46.2: Vortrag

Freitag, 5. April 2019, 09:45–10:00, H31

Transient birefringence and dichroism of ZnO studied by femtosecond time-resolved spectroscopic ellipsometry — •Oliver Herrfurth1, Steffen Richter2, Mateusz Rȩbarz2, Shirly Espinoza2, Joshua A. Leveillee3, André Schleife3, Jakob Andreasson2,4, Marius Grundmann1, and Rüdiger Schmidt-Grund11Universität Leipzig, Felix-Bloch-Institut für Festkörperphysik, Leipzig — 2ELI Beamlines, Institute of Physics, Czech Academy of Science, Prague, Czech Republic — 3Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, USA — 4Condensed Matter Physics, Department of Physics, Chalmers University of Technology, Gothenburg, Sweden

We report on UV-pump-induced transient birefringence and dichroism of an m-plane oriented ZnO thin film measured by femtosecond pump-probe spectroscopic ellipsometry in the spectral range from 340 nm to 690 nm (1.8 eV to 3.6 eV) with approximately 100 fs time-resolution. The pump-induced density of electron-hole pairs is estimated as 3×1019cm−3. We determine the complex dielectric function tensor from measurements parallel and perpendicular to the crystal’s optic axis using a transfer matrix algorithm. Comparison to the ZnO bandstructure and first-principles dielectric function (DF) calculations provides evidence for inter-valence-band transitions of "hot" charge carriers near the M point in the Brillouin zone. They are governed by selection rules for dipole transitions for perpendicular and parallel light polarization which cause the transient optical anisotropy.

100% | Mobil-Ansicht | English Version | Kontakt/Impressum/Datenschutz
DPG-Physik > DPG-Verhandlungen > 2019 > Regensburg