Experimental electronic structure of the electrically switchable antiferromagnet CuMnAs

• Published in: npj quantum materials Vol. 8; no. 1; pp. 19 - 8
• Main Authors: Linn, A. Garrison, Hao, Peipei, Gordon, Kyle N., Narayan, Dushyant, Berggren, Bryan S., Speiser, Nathaniel, Reimers, Sonka, Campion, Richard P., Novák, Vít, Dhesi, Sarnjeet S., Kim, Timur K., Cacho, Cephise, Šmejkal, Libor, Jungwirth, Tomáš, Denlinger, Jonathan D., Wadley, Peter, Dessau, Daniel S.
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group 03.05.2023; Nature Portfolio
• Subjects: Antiferromagnetism; Band theory; Chemical potential; Density functional theory; electronic properties and materials; Electronic structure; Electrons; Energy; Equilibrium; Fermi surfaces; Fermions; Low energy electron diffraction; magnetic properties and materials; MATERIALS SCIENCE; Microscopy; Photoelectric emission; Physics; Room temperature; Single crystals; Spectrum analysis; Symmetry; Thin films
• ISSN: 2397-4648; 2397-4648
• DOI: 10.1038/s41535-023-00554-x

Abstract Tetragonal CuMnAs is a room temperature antiferromagnet with an electrically reorientable Néel vector and a Dirac semimetal candidate. Direct measurements of the electronic structure of single-crystalline thin films of tetragonal CuMnAs using angle-resolved photoemission spectroscopy (ARPES) are reported, including Fermi surfaces (FS) and energy-wavevector dispersions. After correcting for a chemical potential shift of ≈− 390 meV (hole doping), there is excellent agreement of FS, orbital character of bands, and Fermi velocities between the experiment and density functional theory calculations. In addition, 2×1 surface reconstructions are found in the low energy electron diffraction (LEED) and ARPES. This work underscores the need to control the chemical potential in tetragonal CuMnAs to enable the exploration and exploitation of the Dirac fermions with tunable masses, which are predicted to be above the chemical potential in the present samples.