Low-field formation of room-temperature biskyrmions in centrosymmetric MnPdGa magnet

Abstract

Magnetic skyrmions, a kind of localized spin texture topologically protected in magnetic materials, characterized by smaller size and much lower manipulating current density in comparison with ferromagnetic domain walls, are highlighted as potential information carriers for high-density magnetic storage devices. For technological applications, the stabilization of skyrmions in a temperature range around room temperature under a low magnetic field is essential. Here, we demonstrate the formation of magnetic biskyrmions in a low magnetic field at room temperature in a centrosymmetric hexagonal MnPdGa magnet via Lorentz transmission electron microscopy in combination with transport and magnetic measurements. High-density biskyrmions are generated at 300 K in a magnetic field of 0.15 T. In addition, biskyrmions can be generated from ferromagnetic domains and partly remained at zero field when the magnetic field is decreased. A large topological Hall resistivity is observed near room temperature. Furthermore, a wide temperature and magnetic-field window for biskyrmions is deduced from transport and magnetic properties. The simultaneous features of high-density and low magnetic field near room temperature in a single-component material make MnPdGa a promising candidate for future skyrmion-based topological spintronic applications.