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Abstract Room‐temperature magnetic skyrmion materials exhibiting robust topological Hall effect (THE) are crucial for novel nano‐spintronic devices. However, such skyrmion‐hosting materials are rare in nature. In this study, a self‐intercalated transition metal dichalcogenide Cr1+xTe2with a layered crystal structure that hosts room‐temperature skyrmions and exhibits large THE is reported. By tuning the self‐intercalate concentration, a monotonic control of Curie temperature from 169 to 333 K and a magnetic anisotropy transition from out‐of‐plane to the in‐plane configuration are achieved. Based on the intercalation engineering, room‐temperature skyrmions are successfully created in Cr1.53Te2with a Curie temperature of 295 K and a relatively weak perpendicular magnetic anisotropy. Remarkably, a skyrmion‐induced topological Hall resistivity as large as ≈106 nΩ cm is observed at 290 K. Moreover, a sign reversal of THE is also found at low temperatures, which can be ascribed to other topological spin textures having an opposite topological charge to that of the skyrmions. Therefore, chromium telluride can be a new paradigm of the skyrmion material family with promising prospects for future device applications.
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Unconventional Anomalous Hall Effect Driven by Self‐Intercalation in Covalent 2D Magnet Cr 2 Te 3
Abstract Covalent 2D magnets such as Cr2Te3, which feature self‐intercalated magnetic cations located between monolayers of transition‐metal dichalcogenide material, offer a unique platform for controlling magnetic order and spin texture, enabling new potential applications for spintronic devices. Here, it is demonstrated that the unconventional anomalous Hall effect (AHE) in Cr2Te3, characterized by additional humps and dips near the coercive field in AHE hysteresis, originates from an intrinsic mechanism dictated by the self‐intercalation. This mechanism is distinctly different from previously proposed mechanisms such as topological Hall effect, or two‐channel AHE arising from spatial inhomogeneities. Crucially, multiple Weyl‐like nodes emerge in the electronic band structure due to strong spin‐orbit coupling, whose positions relative to the Fermi level is sensitively modulated by the canting angles of the self‐intercalated Cr cations. These nodes contribute strongly to the Berry curvature and AHE conductivity. This component competes with the contribution from bands that are less affected by the self‐intercalation, resulting in a sign change in AHE with temperature and the emergence of additional humps and dips. The findings provide compelling evidence for the intrinsic origin of the unconventional AHE in Cr2Te3 and further establish self‐intercalation as a control knob for engineering AHE in complex magnets.
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- Award ID(s):
- 2242796
- PAR ID:
- 10640988
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Science
- Volume:
- 12
- Issue:
- 2
- ISSN:
- 2198-3844
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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