Noncollinear antiferromagnetic Mn3Sn films

Abstract

Noncollinear hexagonal antiferromagnets with almost zero net magnetization were recently shown to demonstrate giant anomalous Hall effect. Here, we present the structural and magnetic properties of noncollinear antiferromagnetic ${\mathrm{Mn}}_{3}\mathrm{Sn}$ thin films heteroepitaxially grown on Y:${\mathrm{ZrO}}_{2}$ (111) substrates with a Ru underlayer. The ${\mathrm{Mn}}_{3}\mathrm{Sn}$ films were crystallized in the hexagonal $D{0}_{19}$ structure with $c$-axis preferred (0001) crystal orientation. The ${\mathrm{Mn}}_{3}\mathrm{Sn}$ films are discontinuous, forming large islands of approximately 400 nm in width, but are chemical homogeneous and characterized by near perfect heteroepitaxy. Furthermore, the thin films show weak ferromagnetism with an in-plane uncompensated magnetization of $M=34$ kA/m and coercivity of ${\ensuremath{\mu}}_{0}{H}_{\mathrm{c}}=4.0$ mT at room temperature. Additionally, the exchange bias effect was studied in ${\mathrm{Mn}}_{3}\mathrm{Sn}$/Py bilayers. Exchange bias fields up to ${\ensuremath{\mu}}_{0}{H}_{\mathrm{EB}}=12.6$ mT can be achieved at 5 K. These results show ${\mathrm{Mn}}_{3}\mathrm{Sn}$ films to be an attractive material for applications in antiferromagnetic spintronics.