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arXiv · 1906.00257

Transient quantum isolation and critical behavior in the magnetization dynamics of half-metallic manganites

Tommaso Pincelli·Riccardo Cucini·Adriano Verna·Francesco Borgatti·Masaki Oura·Kenji Tamasaku·Tien-lin Lee·Christoph Schlueter·Stefan Günther·Christian Horst Back·Martina Dell'Angela·Roberta Ciprian·Pasquale Orgiani·Aleksandr Petrov·Fausto Sirotti·Valentin Dediu·Ilaria Bergenti·Patrizio Graziosi·Fabio Miletto Granozio·Yoshihito Tanaka·Munetaka Taguchi·Hiroshi Daimon·Jun Fujii·Giorgio Rossi·Giancarlo Panaccione
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Abstract

We combine time resolved pump-probe Magneto-Optical Kerr Effect and Photoelectron Spectroscopy experiments supported by theoretical analysis to determine the relaxation dynamics of delocalized electrons in half-metallic ferromagnetic manganite $La_{1-x}Sr_{x}MnO_{3}$. We observe that the half-metallic character of $La_{1-x}Sr_{x}MnO_{3}$ determines the timescale of both the electronic phase transition and the quenching of magnetization, revealing a quantum isolation of the spin system in double exchange ferromagnets extending up to hundreds of picoseconds. We demonstrate the use of time-resolved hard X-ray photoelectron spectroscopy (TR-HAXPES) as a unique tool to single out the evolution of strongly correlated electronic states across a second-order phase transition in a complex material.

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Tommaso Pincelli, Riccardo Cucini, Adriano Verna, Francesco Borgatti, Masaki Oura, Kenji Tamasaku, Tien-lin Lee, Christoph Schlueter, Stefan Günther, Christian Horst Back, Martina Dell'Angela, Roberta Ciprian, Pasquale Orgiani, Aleksandr Petrov, Fausto Sirotti, Valentin Dediu, Ilaria Bergenti, Patrizio Graziosi, Fabio Miletto Granozio, Yoshihito Tanaka, Munetaka Taguchi, Hiroshi Daimon, Jun Fujii, Giorgio Rossi, Giancarlo Panaccione. 2019-06-01. Transient quantum isolation and critical behavior in the magnetization dynamics of half-metallic manganites. https://doi.org/10.1103/physrevb.100.045118

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