Effect of nematic order on the low-energy spin fluctuations in detwinned BaFe$_{1.935}$Ni$_{0.065}$As$_2$

Wenliang Zhang; J. T. Park; Xingye Lu; Yuan Wei; Xiaoyan Ma; Lijie Hao; Pengcheng Dai; Zi Yang Meng; Yi-feng Yang; Huiqian Luo; Shiliang Li

doi:10.1103/physrevlett.117.227003

arXiv · 1607.06549

Effect of nematic order on the low-energy spin fluctuations in detwinned BaFe$_{1.935}$Ni$_{0.065}$As$_2$

Wenliang Zhang·J. T. Park·Xingye Lu·Yuan Wei·Xiaoyan Ma·Lijie Hao·Pengcheng Dai·Zi Yang Meng·Yi-feng Yang·Huiqian Luo·Shiliang Li

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Abstract

The origin of nematic order remains one of the major debates in iron-based superconductors. In theories based on spin nematicity, one major prediction is that the spin-spin correlation length at (0,$π$) should decrease with decreasing temperature below the structural transition temperature $T_s$. Here we report inelastic neutron scattering studies on the low-energy spin fluctuations in BaFe$_{1.935}$Ni$_{0.065}$As$_2$ under uniaxial pressure. Both intensity and spin-spin correlation start to show anisotropic behavior at high temperature, while the reduction of the spin-spin correlation length at (0,$π$) happens just below $T_s$, suggesting strong effect of nematic order on low-energy spin fluctuations. Our results favor the idea that treats the spin degree of freedom as the driving force of the electronic nematic order.

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Wenliang Zhang, J. T. Park, Xingye Lu, Yuan Wei, Xiaoyan Ma, Lijie Hao, Pengcheng Dai, Zi Yang Meng, Yi-feng Yang, Huiqian Luo, Shiliang Li. 2016-07-22. Effect of nematic order on the low-energy spin fluctuations in detwinned BaFe$_{1.935}$Ni$_{0.065}$As$_2$. https://doi.org/10.1103/physrevlett.117.227003

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