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arXiv · 1804.05769

Ultrafast destruction and recovery of the spin density wave order in iron based pnictides: a multi-pulse optical study

M. Naseska·A. Pogrebna·G. Cao·Z. A. Xu·D. Mihailovic·T. Mertelj
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Abstract

We report on systematic excitation-density dependent all-optical femtosecond time resolved study of the spin-density wave state in iron-based superconductors. The destruction and recovery dynamics are measured by means of the standard and a multi-pulse pump-probe technique. The experimental data are analyzed and interpreted in the framework of an extended three temperature model. The analysis suggests that the optical-phonons energy-relaxation plays an important role in the recovery of almost exclusively electronically driven spin density wave order.

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M. Naseska, A. Pogrebna, G. Cao, Z. A. Xu, D. Mihailovic, T. Mertelj. 2018-04-16. Ultrafast destruction and recovery of the spin density wave order in iron based pnictides: a multi-pulse optical study. https://doi.org/10.1103/physrevb.98.035148

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