Optical Readout of the Néel Vector in the Metallic Antiferromagnet Mn2Au

• DOI: 10.1103/physrevapplied.16.014037
• Publication Date: 2021-07-15T14:58:49Z
• Authors: Vladimir Grigorev; Mariia Filianina; Stanislav Yu. Bodnar; Sergei Sobolev; Nilabha Bhattacha...; Satya Bommanaboyena; Yaryna Lytvynenko; Yurii Skourski; Dirk Fuchs; Mathias Kläui; Martin Jourdan; Jure Demsar
• Keywords: Condensed Matter - Materials Science; Condensed Matter - Mesoscale and Nanoscale Physics; 530 Physics; ddc:530; 0103 physical sciences; 530 Physik; 530; 01 natural sciences

Metallic antiferromagnets with broken inversion symmetry on the two sublattices, strong spin-orbit coupling and high N\'{e}el temperatures offer new opportunities for applications in spintronics. Especially Mn$_{2}$Au, with high N\'{e}el temperature and conductivity, is particularly interesting for real-world applications. Here, manipulation of the orientation of the staggered magnetization,\textit{\ i.e.} the N\'{e}el vector, by current pulses has been recently demonstrated, with the read-out limited to studies of anisotropic magnetoresistance or X-ray magnetic linear dichroism. Here, we report on the in-plane reflectivity anisotropy of Mn$_{2}$Au (001) films, which were N\'{e}el vector aligned in pulsed magnetic fields. In the near-infrared, the anisotropy is $\approx$ 0.6\%, with higher reflectivity for the light polarized along the N\'{e}el vector. The observed magnetic linear dichroism is about four times larger than the anisotropic magnetoresistance. This suggests the dichroism in Mn$_{2}$Au is a result of the strong spin-orbit interactions giving rise to anisotropy of interband optical transitions, in-line with recent studies of electronic band-structure. The considerable magnetic linear dichroism in the near-infrared could be used for ultrafast optical read-out of the N\'{e}el vector in Mn$_{2}$Au.