Emergence of the topological Hall effect in a tetragonal compensated ferrimagnet Mn2.3Pd0.7Ga

Topological spin textures such as magnetic skyrmions have attracted considerable interest due to their potential application in spintronic devices. However, there still remain several challenges to overcome before their practical application, for instance, achieving high scalability and thermal stability. Recent experiments have proposed a new class of skyrmion materials in the Heusler family, Mn 1.4 Pt 0.9 Pd 0.1 Sn and Mn 2 Rh 0.95 Ir 0.05 Sn, which possess noncollinear magnetic structures. Motivated by these experimental results, we suggest another Heusler compound hosted by Mn 3 Ga to overcome the above limitations. We fabricate Mn 3- x Pd x Ga thin films, focusing on the magnetic compensation point. In Mn 2.3 Pd 0.7 Ga, we find a spin-reorientation transition around T SR = 320 K. Below the T SR , we observe the topological Hall effect and a positive magnetic entropy change, which are the hallmarks of a chiral noncollinear spin texture. By integrating all the data, we determine the magnetic phase diagram, displaying a wide chiral noncollinear spin phase even at room temperature. We believe that this compensated ferrimagnet shows promise for opening a new avenue toward chiral spin-based, high-density, and low-power devices. Spintronics: Alloys start to warm up An alloy with room temperature properties useful in energy-efficient information processing has been developed by scientists in South Korea. Materials obtain their magnetic properties from an intrinsic property of fundamental particles called spin. Harnessing spin for information processing, known as spintronics, offers a low-power complement to conventional electronics but finding materials exhibiting appropriate stable magnetic properties at everyday temperatures is challenging. Myung-Hwa Jung and colleagues from Sogang University in Seoul have created a material in which the spins are arranged into a distinct pattern at room temperature. The material consisted of thin films of a gallium–manganese alloy which were then ‘doped’ with palladium to form Mn 2.3 Pd 0.7 Ga. The team observed that the spins formed chiral patterns useful for spintronics at temperatures up to approximately 47 °C. The tetragonal Mn 3-x Pd x Ga becomes compensated ferrimagnet at x = 0.7. In the compensated ferrimagnet, Mn 2.3 Pd 0.7 Ga, we observed spin reorientation and topological Hall effect due to the strong spin-orbit coupling and inversion symmetry breaking by Pd atoms. We revealed that this additional Hall behavior