Qdev seminar by Filip Krizek, Institute of Physics of the Czech Academy of Sciences

Atomically sharp domain walls in CuMnAs

High quality thin films of tetragonal antiferromagnetic CuMnAs [1] grown by molecular beam epitaxy, were recently implemented into novel Spintronic devices. These rely on different interesting phenomena, as are for example Néel vector reorientation via spin-orbit coupling [2] or thermal Quenching into high resistivity states [3].

I will present the full story of the development CuMnAs, which is the workhorse material of antiferromagnetic spintronics. One of the latest highlights are transmission electron microscopy measurements of the magnetic structure of epitaxial CuMnAs thin films at the atomic scale, which allowed us to demonstrate the existence of atomically sharp antiferromagnetic domain walls [4]. These novel magnetic objects do not only help us to explain the physical mechanisms behind the interesting functionalities of CuMnAs based devices [5], but also provide an important insight into the crystalline/magnetic structure interplay in magnetic materials.

[1] Krizek, et al., Molecular Beam Epitaxy of CuMnAs, Physical Review Materials 2020, 4 (1), 014409.

[2] Wadley, et al., Electrical Switching of an antiferromagnet, Science 2016, 351(6273):587-90.

[3] Kašpar, et al., Quenching of an antiferromagnet into high resistivity states using electrical or ultrashort optical pulses, Nature Electronics 2020, 4 (1), 30-37.

[4] Krizek, et al., Atomically sharp domain walls in an antiferromagnet, Science Advances 2022, 8 (13), eabn3535.

[5] Zubáč, et al., Hysteretic effects and magnetotransport of electrically switched CuMnAs, Physical Review B, 2021, 104 (18), 184424.