Quantum Electronics and Spintronics
This project aims at creating new topological magnets showing gigantic electrical and magnetic responses. Manipulation of their nanoscale domain structures may lay the foundation for conceptually new spintronic devices with unprecedented energy efficiency and storage capacity, bringing in a new era of information technology. In particular, antiferromagnetic materials allow designs of much more highly integrated and high-speed memory cells than commonly used ferromagnetic counterparts. Based on our discoveries of new materials with fascinating functions, our project aims at forming a new scheme of nonvolatile memory, logic circuit, beyond 5G technology necessary for creating our smart and sustainable society.
Fig.１ Schematic figures of anomalous Hall effect (AHE) in (a) ferromagnets, (b) antiferromagnets, and (c) Weyl antiferromagnets. Generally, anomalous Hall effects scale with a magnetization. Ferromagnets show the large AHE (a). Antiferromagnets generally do not show the sizable AHE since they have almost no magnetization (b). Weyl antiferromagnets show the fictitious field induced large AHE, which is comparable that observed in ferromagnets (c).
Fig.2 Current induced switching of the anomalous Hall effect in the Mn3Sn/nonmagnetic-metal bilayer devices. (a) Hall voltage vs write current for the Mn3Sn/Pt, Mn3Sn/Cu and Mn3Sn/W devices at room temperature. (b) Multi-level switching in the Mn3Sn/Pt devices.