Wang, J., Yang, X., Yang, Z., Lu, J., Ho, P., Wang, W., Ang, Y. S., Cheng, Z., & Fang, S. (2025). Pentagonal 2D Altermagnets: Material Screening and Altermagnetic Tunneling Junction Device Application. Advanced Functional Materials. Portico. https://doi.org/10.1002/adfm.202505145
Abstract:
Altermagnetism, the third magnetic phase beyond ferromagnetism and antiferromagnetism, holds great promise for spintronics but also faces challenges in materials discovery and mechanism exploration. Here, through high‐throughput screening of 170 pentagonal 2D materials, 4 altermagnetic semiconductors (MnS2, CoS2, MnC2, and CoPSe) are identified with sizable spin splitting (109–172 meV). It is shown that MnS2 is the first‐of‐kind altermagnetic second‐order topological insulator (AMSOTI), as evidenced by a nontrivial real Chern number (νR = 1) and spin‐polarized corner state. Using ab inito quantum transport simulation, a MnS2‐based altermagnetic tunneling junction (AMTJ) is designed and a giant tunneling magnetoresistance (TMR) of 1.5 × 105% at the Fermi level, which surpasses MF2 (M = Co and Ni)‐based AMTJ by three orders of magnitude. In addition, by applying a twisting angle of 90° to the AMTJ without altering the order, a significant TMR of 1.2 × 107% as driven by the structural changes is observed. This work unveils pentagonal 2D materials as a compelling material platform for exploring the physics and device applications of altermagnets.
License type:
Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)
Funding Info:
This research / project is supported by the Agency for Science, Technology and Research - RIE2025 Manufacturing, Trade and Connectivity Individual Research Grant
Grant Reference no. : M23M6c0101
This research / project is supported by the Agency for Science, Technology and Research - RIE2025 Manufacturing, Trade and Connectivity Individual Research Grant
Grant Reference no. : M24N7c0086