Observation of Colossal Topological Hall Effect in Noncoplanar Ferromagnet Cr_5Te_6 Thin Films

摘要

The topological Hall effect (THE) is critical to the exploration of the spinchirality generated by the real-space Berry curvature, which has attractedworldwide attention for its prospective applications in spintronic devices.However, the prominent THE remains elusive at room temperature, whichseverely restricts the practical integration of chiral spin textures. Here, acolossal intrinsic THE is showed up to ≈1.6 μΩ cm in large-area ferromagnetCr_5Te_6 thin films epitaxially grown by pulsed laser deposition. Such a THE canbe maintained until 270 K, which is attributed to the field-stimulated noncoplanarspin textures induced by the interaction of the in-plane ferromagnetand antiferromagnet infrastructures. The first-principles calculations furtherverify the considerable Dzyaloshinskii-Moriya interaction in Cr_5Te_6. This worknot only paves the way for robust chiral spin textures near room temperaturein large-area low-dimensional ferromagnetic films for practical applications,but also facilitates the development of high-density and dissipationless spintronicdevices.