Julie Karel, Monash
The kagome magnet TbMn6Sn6 exhibits a near-perfect structure for exploring topological Chern physics, which features a Mn kagome plane and a nearby perpendicular magnetic anisotropic Tb layer below 310 K (the spontaneous spin reorientation transition “point”, T SR ).
Scanning tunnelling microscopy/spectroscopy has confirmed the presence of Chern gap and chiral boundary states within TbMn6Sn6. Additionally, the Berry curvature, generated by the gapped Dirac cone, contributes to intrinsic effects like the giant anomalous Hall effect and the giant anomalous Nernst effect, among others.
In this study, we present a giant nonlinear Hall effect in TbMn6Sn6 occurring near T SR , which includes the room temperature. The SR transition allows manipulation of the orientation of Tb and Mn moments between the c-axis and the a-axis by applying a small magnetic field.
We have employed focused ion beam lithography to fabricate micron-sized Hall-bar devices with current flowing along either the a-axis or the c-axis. Our temperature-, magnetic-field-, and electronic-current-dependent investigations reveal that the quantum magnet TbMn6Sn6 can be precisely tuned at room temperature, and thus holds significant potential for high-efficiency spintronic applications.
About the presenter
CI Dr Julie Karel conducts research at the intersection of materials science and condensed matter physics to develop new materials for emerging low-energy nanoelectronic and magnetoelectronic devices. Her approach to materials design is to utilise complete structural disorder to modify the magnetic and electronic properties of materials.
Within FLEET, Dr Karel will primarily be involved in Research theme 1, Topological materials and Enabling Technology B, Nanodevice fabrication, working closely with both CIs Nagy Valanoor at UNSW and Lan Wang at RMIT. She will use her expertise in ionic liquid gating and electronic and magneto-transport to study multiferroic materials (Valanoor) and materials exhibiting large spin orbit torques (Wang).