Abstract
Topological insulators (TI) and magnetic topological insulators (MTI) can apply highly efficient spin-orbit torque (SOT) and manipulate the magnetization with their unique topological surface states (TSS) with ultrahigh efficiency. Here, efficient SOT switching of a hard MTI, V-doped (Bi,Sb)2Te3 (VBST), with a large coercive field that can prevent the influence of an external magnetic field, is demonstrated. A giant switched anomalous Hall resistance of 9.2 kΩ is realized, among the largest of all SOT systems, which makes the Hall channel a good readout and eliminates the need to fabricate complicated magnetic tunnel junction (MTJ) structures. The SOT switching current density can be reduced to 2.8 × 105Acm−2, indicating its high efficiency. Moreover, as the Fermi level is moved away from the Dirac point by both gate and composition tuning, VBST exhibits a transition from edge-state-mediated to surface-state-mediated transport, thus enhancing the SOT effective field to (1.56 ± 0.12) × 10−6TA−1cm2 and the interfacial charge-to-spin conversion efficiency to 3.9 ± 0.3 nm−1. The findings establish VBST as an extraordinary candidate for energy-efficient magnetic memory devices.
Original language | English (US) |
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Article number | 2406772 |
Journal | Advanced Materials |
Volume | 36 |
Issue number | 46 |
DOIs | |
State | Published - Nov 14 2024 |
Externally published | Yes |
Bibliographical note
Publisher Copyright:© 2024 Wiley-VCH GmbH.
Keywords
- current-induced switching
- hard ferromagnets
- magnetic topological insulators
- spin-orbit torque
- topological surface states
PubMed: MeSH publication types
- Journal Article