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arXiv · 1402.5811

Spectrally-resolved femtosecond reflectivity relaxation dynamics in undoped SDW 122-structure iron based pnictides

A. Pogrebna·N. Vujičić·T. Mertelj·G. Cao·Z. A. Xu·J. -H. Chu·I. R. Fisher·D. Mihailovic
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Abstract

We systematically investigate temperature- and spectrally-dependent optical reflectivity dynamics in AAs$_{2}$Fe$_{2}$, (A=Ba, Sr and Eu), iron-based superconductors parent spin-density-wave (SDW) compounds. Two different relaxation processes are identified. The behavior of the slower process, which is strongly sensitive to the magneto-structural transition, is analyzed in the framework of the relaxation-bottleneck model involving magnons. The results are compared to recent time resolved angular photoemission results (TR-ARPES) and possible alternative assignment of the slower relaxation to the magneto-structural order parameter relaxation is discussed.

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A. Pogrebna, N. Vujičić, T. Mertelj, G. Cao, Z. A. Xu, J. -H. Chu, I. R. Fisher, D. Mihailovic. 2014-02-24. Spectrally-resolved femtosecond reflectivity relaxation dynamics in undoped SDW 122-structure iron based pnictides. https://doi.org/10.1103/physrevb.89.165131

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