Optically Triggered Néel Vector Manipulation of a Metallic Antiferromagnet Mn2Au under Strain

Vladimir Grigorev (1, 2) , Mariia Filianina (1, 2) , Yaryna Lytvynenko (1, 3) , Sergei Sobolev (1) , Amrit Raj Pokharel (1) , Amon Lanz (1) , Alexey Sapozhnik (4) , Stanisalv Bodnar (5) , Armin Kleibert (6) , Petr Grigorev (7, 8) , Yurii Skourski (9) , Mathias Kläui (1, 2) , Hans-Joachim Elmers (1, 2) , Martin Jourdan (1) , Jure Demsar (1, 2)

1 Institute of Physics, University of Mainz
2 Graduate School Materials Science [Mainz, Germany]
3 Institute of Magnetism of the NAS and MES of Ukraine - institute if magnetism
4 EPFL - Ecole Polytechnique Fédérale de Lausanne
5 WSI - Walter Schottky Institut
6 Paul Scherrer Institute, Swiss Light Source
7 CINaM - Centre Interdisciplinaire de Nanoscience de Marseille
8 CNRS - Centre National de la Recherche Scientifique
9 Dresden High Magnetic Field Laboratory

The absence of stray fields, their insensitivity to external magnetic fields, and ultrafast dynamics make antiferromagnets promising candidates for active elements in spintronic devices. Here, we demonstrate manipulation of the Néel vector in the metallic collinear antiferromagnet Mn2Au by combining strain and femtosecond laser excitation. Applying tensile strain along either of the two in-plane easy axes and locally exciting the sample by a train of femtosecond pulses, we align the Néel vector along the direction controlled by the applied strain. The dependence on the laser fluence and strain suggests the alignment is a result of optically-triggered depinning of 90o domain walls and their sliding in the direction of the free energy gradient, governed by the magneto-elastic coupling. The resulting, switchable, state is stable at room temperature and insensitive to magnetic fields. Such an approach may provide ways to realize robust high-density memory device with switching timescales in the picosecond range.

Domaines: Matière Condensée [cond-mat]

Vladimir Grigorev, Mariia Filianina, Yaryna Lytvynenko, Sergei Sobolev, Amrit Raj Pokharel, et al.. Optically Triggered Néel Vector Manipulation of a Metallic Antiferromagnet Mn2Au under Strain. ACS Nano, 2022, ⟨10.1021/acsnano.2c07453⟩. ⟨hal-03885557⟩