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arXiv · 1304.2866

Normal state bottleneck and nematic fluctuations from femtosecond quasi-particle relaxation dynamics in Sm(Fe,Co)AsO

T. Mertelj·L. Stojchevska·N. D. Zhigadlo·J. Karpinski·D. Mihailovic
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Abstract

We investigate temperature and fluence dependent dynamics of the photoexcited quasi-particle relaxation and low-energy electronic structure in electron-doped 1111-structure Sm(Fe_{0.93}Co_{0.07})AsO single crystal. We find that the behavior is qualitatively identical to the 122-structure Ba(Fe,Co)_{2}As_{2} including the presence of a normal state pseudogap and a marked 2-fold symmetry breaking in the tetragonal phase that we relate to the electronic nematicity. The 2-fold symmetry breaking appears to be a general feature of the electron doped iron pnictides.

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T. Mertelj, L. Stojchevska, N. D. Zhigadlo, J. Karpinski, D. Mihailovic. 2013-04-10. Normal state bottleneck and nematic fluctuations from femtosecond quasi-particle relaxation dynamics in Sm(Fe,Co)AsO. https://doi.org/10.1103/physrevb.87.174525

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