Tunable magnetic and transport properties of Mn3Ga thin films on Ta/Ru seedlayer

Abstract

Hexagonal D019-type Mn3Z alloys that possess large anomalous and topological-like Hall effects have attracted much attention due to their great potential in the antiferromagnetic spintronic devices. Here, we report the preparation of Mn3Ga film in both tetragonal and hexagonal phases with a tuned Ta/Ru seed layer on the thermally oxidized Si substrate. A large coercivity together with a large anomalous Hall resistivity is found in the Ta-only sample with mixed tetragonal phase. By increasing the thickness of Ru layer, the tetragonal phase gradually disappears and a relatively pure hexagonal phase is obtained in the Ta(5)/Ru(30) buffered sample. Further magnetic and transport measurements revealed that the anomalous Hall conductivity nearly vanishes in the pure hexagonal sample, while an abnormal asymmetric hump structure emerges in the low field region. The extracted additional Hall term is robust in a large temperature range and presents a sign reversal above 200K. The abnormal Hall properties are proposed to be closely related with the frustrated spin structure of D019 Mn3Ga.

References in corpus (4)

• Interface-driven topological Hall effect in SrRuO${}_3$-SrIrO${}_3$ bilayer
• Robust formation of skyrmions and topological Hall effect in epitaxial thin films of MnSi
• Strong, anisotropic anomalous Hall effect and spin Hall effect in chiral antiferromagnetic compounds Mn${}_{3}X$ ($X$ = Ge, Sn, Ga, Ir, Rh and Pt)
• A centrosymmetric hexagonal magnet with superstable biskyrmion magnetic nanodomains in a wide temperature range of 100K to 340K

Cited by in corpus (1)

• Cluster magnetic octupole induced out-of-plane spin polarization in antiperovskite antiferromagnet