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

**Authors:** Tommaso Pincelli, Riccardo Cucini, Adriano Verna, Francesco Borgatti,, Masaki Oura, Kenji Tamasaku, Tien-lin Lee, Christoph Schlueter, Stefan, G\"unther, 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

arXiv: 1906.00257 · 2019-07-17

## TL;DR

This study investigates the ultrafast magnetization dynamics in half-metallic manganites, revealing quantum isolation effects and demonstrating the effectiveness of time-resolved spectroscopy techniques in probing electronic phase transitions.

## Contribution

It combines experimental and theoretical approaches to uncover the quantum isolation of spin systems and introduces TR-HAXPES as a novel tool for studying electronic state evolution.

## Key findings

- Half-metallic character influences relaxation timescales.
- Quantum isolation of spin system extends up to hundreds of picoseconds.
- TR-HAXPES effectively probes electronic state changes during phase transition.

## 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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Source: https://tomesphere.com/paper/1906.00257