Regensburg 2016 – wissenschaftliches Programm

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

TT: Fachverband Tiefe Temperaturen

TT 78: Correlated Electrons: Poster Session

TT 78.16: Poster

Donnerstag, 10. März 2016, 15:00–18:30, Poster D

Hints for a pressure-induced phase transition in the honeycomb lattice iridate Na₂IrO₃ probed by infrared microspectroscopy — •Volker Hermann¹, Jihaan Ebad-Allah^1,2, Friedrich Freund¹, Philipp Gegenwart¹, and Christine Kuntscher¹ — ¹Universität Augsburg, 86159 Augsburg, Germany — ²Department of Physics, University of Tanta, 31527 Tanta, Egypt

Honeycomb lattice iridates A₂IrO₃ with A=Na, Li, Sr,... are discussed in terms of topological insulators and Mott insulators due to their strong spin-orbit coupling [1,2]. Na₂IrO₃ has a layered honeycomb structure with edge-sharing IrO₆ octahedra. We have carried out pressure-dependent reflection and transmission measurements on monocrystalline Na₂IrO₃ in the infrared and visible frequency ranges. With increasing pressure the phonon modes harden and the Ir 5d crystal field excitations change only slighly. Several observations suggest the occurrence of a pressure-induced phase transition, including splitting and screening of phonon modes.
Ch. H. Kim et al., PRL 108, 106401 (2012)
Y. Singh and P. Gegenwart, PRB 82, 064412 (2010)