Anomalous Hall effect in nanoscale structures of the antiferromagnetic Weyl semimetal Mn₃Sn at room temperature

The magnetic Weyl semimetallic state in the chiral antiferromagnet Mn₃Sn has attracted interest for its potential in memory technology. Despite vanishingly small magnetization, the material exhibits large transverse responses that can be electrically manipulated, similar to ferromagnets. Through deposition on heated Si/SiO₂ substrates, we have fabricated polycrystalline Mn₃Sn films that have coarse surfaces, the thinner of which have a discontinuous structure comprised of grains with diameters of the order of 100 nm. We confirm that these grains retain the anomalous Hall effect arising in the time reversal symmetry broken chiral antiferromagnetic phase of Mn₃Sn at room temperature by serially connecting the grains with an additional conducting layer. These results pave the path for the potential applications of nanoscale Mn₃Sn systems, which could be useful in the development of energy efficient memory devices.