Magnetic moment evolution and spin freezing in doped BaFe$_{2}$As$_{2}$

Jonathan Pelliciari; Yaobo Huang; Kenji Ishii; Chenglin Zhang; Pengcheng Dai; Gen Fu Chen; Lingyi Xing; Xiancheng Wang; Changqing Jin; Hong Ding; Philipp Werner; Thorsten Schmitt

doi:10.1038/s41598-017-07286-6

arXiv · 1607.04038

Magnetic moment evolution and spin freezing in doped BaFe$_{2}$As$_{2}$

Jonathan Pelliciari·Yaobo Huang·Kenji Ishii·Chenglin Zhang·Pengcheng Dai·Gen Fu Chen·Lingyi Xing·Xiancheng Wang·Changqing Jin·Hong Ding·Philipp Werner·Thorsten Schmitt

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Abstract

Fe-K$_{\beta}$ X-ray emission spectroscopy measurements reveal an asymmetric doping dependence of the magnetic moments $\mu_\text{bare}$ in electron- and hole-doped BaFe$_{2}$As$_{2}$. At low temperature, $\mu_\text{bare}$ is nearly constant in hole-doped samples, whereas it decreases upon electron doping. Increasing temperature substantially enhances $\mu_\text{bare}$ in the hole-doped region, which is naturally explained by the theoretically predicted crossover into a spin-frozen state. Our measurements demonstrate the importance of Hund's coupling and electronic correlations, especially for hole-doped BaFe$_{2}$As$_{2}$, and the inadequacy of a fully localized or fully itinerant description of the 122 family of Fe pnictides.

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Jonathan Pelliciari, Yaobo Huang, Kenji Ishii, Chenglin Zhang, Pengcheng Dai, Gen Fu Chen, Lingyi Xing, Xiancheng Wang, Changqing Jin, Hong Ding, Philipp Werner, Thorsten Schmitt. 2016-07-14. Magnetic moment evolution and spin freezing in doped BaFe$_{2}$As$_{2}$. https://doi.org/10.1038/s41598-017-07286-6

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