ARPES and DFT study of the electronic structure of the electronically switchable antiferromagnet, CuMnAs*

Tetragonal CuMnAs is a room temperature antiferromagnet with an electrically reorientable Néel vector. 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 E-k dispersions.  After correcting for an unexpected 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.  Additionally, 2x1 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 topological quantum switching of the Dirac point predicted to be above the chemical potential in the current samples.