We investigate the evolution of a photoexcitation in correlated materials over a wide range of time scales. The system studied is a one-dimensional model of a manganite with correlated electron, spin, orbital, and lattice degrees of freedom, which we relate to the three-dimensional material Pr1−xCaxMnO3. The ground-state phases for the entire composition range are determined and rationalized by a coarse-grained polaron model. At half-doping a pattern of antiferromagnetically coupled Zener polarons is realized. Using time-dependent density-matrix renormalization group (tDMRG), we treat the electronic quantum dynamics following the excitation. The emergence of quasiparticles is addressed, and the relaxation of the nonequilibrium quasiparticle distribution is investigated via a linearized quantum-Boltzmann equation. Our approach shows that the magnetic microstructure caused by the Zener polarons leads to an increase of the relaxation times of the excitation.
@article{arxiv.1610.07246,
title = {Relaxation of photoexcitations in polaron-induced magnetic microstructures},
author = {Thomas Köhler and Sangeeta Rajpurohit and Ole Schumann and Sebastian Paeckel and Fabian R. A. Biebl and Mohsen Sotoudeh and Stephan C. Kramer and Peter E. Blöchl and Stefan Kehrein and Salvatore R. Manmana},
journal= {arXiv preprint arXiv:1610.07246},
year = {2018}
}