Regensburg 2019 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
MA: Fachverband Magnetismus
MA 15: Magnetism Poster A
MA 15.51: Poster
Dienstag, 2. April 2019, 10:00–13:00, Poster E
Phase transition dynamics of CMR manganites — •Tommaso Pincelli1,2, Gian Marco Pierantozzi2, Chiara Bigi2,3, Riccardo Cucini2, Francesco Borgatti4, Aleksandr Yu. Petrov2, Christian H. Back5, Masaki Oura6, Giorgio Rossi2,3, and Giancarlo Panaccione2 — 1Fritz-Haber-Institut of MPG, Faradayweg 4-6, 14195 Berlin, Germany — 2Istituto Officina dei Materiali of CNR, c/o Area Science Park, S.S.14 km 163,5 - I-34149 Trieste, Italy — 3Dipartimento di Fisica, Università di Milano, Via Celoria 16, I-20133 Milano - Italy — 4Istituto per lo Studio dei Materiali Nanostrutturati of CNR, via P. Gobetti 101, I-40129 Bologna, Italy — 5Department of Physics, Technical University Munich, D-85748 Garching b. München, Germany — 6RIKEN SPring-8 Center, Kouto 1-1-1, Sayo-cho, Sayo-gun, Hyogo 679-5148, Japan
In CMR manganites, delocalization of electronic states results from competing double-exchange-driven delocalization and polaronic trapping. We explore the dynamics of the ferromagnetic metal-paramagnetic bad-metal phase transition. In the wide-band half-metallic La(1-x)Sr(x)MnO3 we isolate the evolution of delocalized electronic states with time-resolved hard x-ray photoemission, showing that the slow collapse of magnetization keeps the double-exchange interaction active for several hundreds of picoseconds, suggesting a slow timescale evolution of electronic correlation. When competing polaron trapping is brought into play in the narrow-band La(1-x)Ca(x)MnO3, new metastable phases emerge, optically accessible on ultrafast timescales.