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arXiv · 1603.07873

The influence of the structural transition on magnetic fluctuations in NaFeAs

Juanjuan Liu·Jinchen Wang·Wei Luo·Jieming Sheng·Aifeng Wang·Xianhui Chen·Sergey A. Danilkin·Wei Bao
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Abstract

NaFeAs belongs to a class of Fe-based superconductors which parent compounds show separated structural and magnetic transitions. Effects of the structural transition on spin dynamics therefore can be investigated separately from the magnetic transition. A plateau in dynamic spin response is observed in a critical region around the structural transition temperature T_S. It is interpreted as due to the stiffening of spin fluctuations along the in-plane magnetic hard axis due to the dxz and dyz orbital ordering. The appearance of anisotropic spin dynamics in the critical region above the T_S at T* offers a dynamic magnetic scattering mechanism for anisotropic electronic properties in the commonly referred "nematic phase".

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Juanjuan Liu, Jinchen Wang, Wei Luo, Jieming Sheng, Aifeng Wang, Xianhui Chen, Sergey A. Danilkin, Wei Bao. 2016-03-25. The influence of the structural transition on magnetic fluctuations in NaFeAs. https://doi.org/10.1088/0953-8984%2F28%2F27%2F27lt01

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