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arXiv · 1807.01471

Spin Waves in Detwinned BaFe$_2$As$_2$

Xingye Lu·Daniel D. Scherer·David W. Tam·Wenliang Zhang·Rui Zhang·Huiqian Luo·Leland W. Harriger·H. C. Walker·D. T. Adroja·Brian M. Andersen·Pengcheng Dai
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Abstract

Understanding magnetic interactions in the parent compounds of high-temperature superconductors forms the basis for determining their role for the mechanism of superconductivity. For parent compounds of iron pnictide superconductors such as $A$Fe$_2$As$_2$ ($A=$ Ba, Ca, Sr), although spin excitations have been mapped out throughout the entire Brillouin zone (BZ), measurements were carried out on twinned samples and did not allow for a conclusive determination of the spin dynamics. Here we use inelastic neutron scattering to completely map out spin excitations of $\sim$100\% detwinned BaFe$_2$As$_2$. By comparing observed spectra with theoretical calculations, we conclude that the spin excitations can be well described by an itinerant model with important contributions from electronic correlations.

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Xingye Lu, Daniel D. Scherer, David W. Tam, Wenliang Zhang, Rui Zhang, Huiqian Luo, Leland W. Harriger, H. C. Walker, D. T. Adroja, Brian M. Andersen, Pengcheng Dai. 2018-07-04. Spin Waves in Detwinned BaFe$_2$As$_2$. https://doi.org/10.1103/physrevlett.121.067002

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