Confinement effects on the antichiral spin structure in epitaxial c-Mn₃Sn thin films

The field of topological magnetic materials is one of the most active areas of condensed matter research, with intricate ties to potential future technologies. The discovery of Mn₃Sn as an antiferromagnetic (AFM) Weyl semimetal with unique physical properties, such as large Anomalous Hall (AHE) and Anomalous Nernst Effects (ANE), electrically controlable AFM order, and predicted THz scale spin dynamics, has led to significant efforts in developing the material as a platform for non-volatile memory storage applications [1-4]. We present neutron diffraction studies of magnetic order in c-oriented Mn₃Sn thin films with thicknesses of 150 nm, 30 nm, and 10 nm. These experiments systematically evaluate the impact of thin film confinement on the c-directed low-T magnetic wavevector observed in both bulk single crystals of Mn₃Sn [5] and our previous experiments on a-oriented Mn₃Sn thin films. These studies further establish the utility of neutrons as a probe of magnetism in materials prepared in a device-like format and develops our understanding of Mn₃Sn’s viability as a platform for antiferromagnetic spintronics.

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