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arXiv · 1702.03845

Coexistence of localized and itinerant magnetism in intercalated iron-selenide (Li,Fe)OHFeSe

Da-Yong Liu·Zhe Sun·Liang-Jian Zou
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Abstract

The electronic structure and magnetism of a new magnetic intercalation compound (Li0.8Fe0.2)OHFeSe are investigated theoretically. The electronic structure calculations predict that the Fe in the (Li,Fe)OH intercalated layer is in +2 valence state, i.e. there is electron doping to the FeSe layer, resulting in the shrinking of the Fermi surface (FS) pocket around Gamma and a strong suppression of dynamical spin susceptibility at M in comparison with the bulk FeSe compound. The ground state of the FeSe layer is a striped antiferromagnetic (SAFM) metal, while the (Li,Fe)OH layer displays a very weak localized magnetism, with an interlayer ferromagnetic (FM) coupling between the FeSe and intercalated (Li,Fe)OH layers. Moreover, the (Li,Fe)OH is more than a block layer; it is responsible for enhancing the antiferromagnetic (AFM) correlation in the FeSe layer through interlayer magnetic coupling. We propose that the magnetic spacer layer introduces a tuning mechanism for spin fluctuations associated with superconductivity in iron-based superconductors.

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Da-Yong Liu, Zhe Sun, Liang-Jian Zou. 2017-02-13. Coexistence of localized and itinerant magnetism in intercalated iron-selenide (Li,Fe)OHFeSe. https://doi.org/10.1088/1367-2630%2Faa5a71

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