论文标题
抗氟酸盐层对基于欧盟的1111化合物eutasf中磁顺序的影响（T = Zn，Mn和Fe）
Effect of antifluorite layer on the magnetic order in Eu-based 1111 compounds, EuTAsF (T = Zn, Mn, and Fe)
论文作者
论文摘要
1111化合物具有交替的荧光岩和抗氟众层的序列，是庞大的基于Fe的超导体家族的结构宿主。在这里，我们使用中子粉末衍射和密度功能理论（DFT）的带结构计算来研究[euf]+荧光岩层中EU2+的磁顺序，具体取决于[TAS] - 防氟众层的性质，可以是非磁性半导体（T = Zn），磁性半径（T = Mnagnical）（T = Mn），或磁性（T = mn）。在所有三种EUTASF化合物中确认了由于EU2+磁矩的排序，在Tn〜2.4-3 K处的抗磁磁过渡。 Whereas in EuTAsF (T = Zn and Mn), the commensurate k1 = (1/2 1/2 0) stripe order pattern with magnetic moments within the ab-plane is observed, the order in EuFeAsF is incommensurate with k = (0 0.961(1) 1/2) and represents a cycloid of Eu2+ magnetic moments confined within the bc-plane.此外，EumnASF中的MN2+ sublattice具有强大的G型抗铁磁序，至少持续到室温，并沿C方向带有磁矩。尽管DFT计算表明在Eufeasf的Fe-Sublattice中，条纹抗铁磁序是基态，但中子衍射没有发现与Fe相关的远距离磁顺序的证据。我们表明，相邻[EUF]+层之间令人沮丧的平面相互作用J3与半导体的荧光层层[TAS] - （T = Zn和Mn）相当，并且在金属[金属[FEAS] - [feas] - es-os。后者以及轻微的骨质失真，被认为是在Eufeasf中观察到的不相差的磁结构的起源。
The 1111 compounds with an alternating sequence of fluorite and antifluorite layers serve as structural hosts for the vast family of Fe-based superconductors. Here, we use neutron powder diffraction and density-functional-theory (DFT) band-structure calculations to study magnetic order of Eu2+ in the [EuF]+ fluorite layers depending on the nature of the [TAs]- antifluorite layer that can be non-magnetic semiconducting (T = Zn), magnetic semiconducting (T = Mn), or magnetic metallic (T = Fe). Antiferromagnetic transitions at TN ~ 2.4 - 3 K due to an ordering of the Eu2+ magnetic moments were confirmed in all three EuTAsF compounds. Whereas in EuTAsF (T = Zn and Mn), the commensurate k1 = (1/2 1/2 0) stripe order pattern with magnetic moments within the ab-plane is observed, the order in EuFeAsF is incommensurate with k = (0 0.961(1) 1/2) and represents a cycloid of Eu2+ magnetic moments confined within the bc-plane. Additionally, the Mn2+ sublattice in EuMnAsF features a robust G-type antiferromagnetic order that persists at least up to room temperature, with magnetic moments along the c-direction. Although DFT calculations suggest stripe antiferromagnetic order in the Fe-sublattice of EuFeAsF as the ground state, neutron diffraction reveals no evidence of long-range magnetic order associated with Fe. We show that the frustrating interplane interaction J3 between the adjacent [EuF]+ layers is comparable with in-plane J1-J2 interactions already in the case of semiconducting fluorite layers [TAs]- (T = Zn and Mn) and becomes dominant in the case of the metallic [FeAs]- ones. The latter, along with a slight orthorhombic distortion, is proposed to be the origin of the incommensurate magnetic structure observed in EuFeAsF.
