Abstract
Electrides constitute a unique class of materials that can be developed as conventional superconductors with diverse dimensional superconductivity. However, the transition temperatures of electride superconductors are generally low and promoting their usually requires extremely high external pressures that are formidable for practical applications. Here, based on the first-principles calculations, we proposed that the recently reported electride, , can exhibit a two-dimensional (2D) superconductivity, which has a of 10.3 K that is the highest ever found for bulk electride superconductors at ambient pressure. More interestingly, we found that the high of is mainly attributed to the large average phonon frequency, rather than the strong electron-phonon coupling, which can be further understood by the small atomic weight of Be atoms and the strong Be-N bonds. Moreover, compared to most conventional superconductors, we identified an unusual dependence of the superconductivity of on external pressures, originating from a unique charge transfer from its cationic framework to its anionic electron cloud. Our studies provide a deeper understanding of the superconductivity of 2D electrides and suggest a feasible way for the development of high-temperature electride superconductors at ambient pressure.
- Received 20 September 2023
- Revised 19 December 2023
- Accepted 20 December 2023
DOI:https://doi.org/10.1103/PhysRevB.109.014504
©2024 American Physical Society