功能化二维六方MBenes的超导电性与能带拓扑
Superconductivity and Band Topology in Functionalized 2D Hexagonal MBenes
- University of Tehran（德黑兰大学）
- Binghamton University-SUNY（宾汉姆顿大学-纽约州立大学）
- JAIST（石川金泽工业大学）
- Institute of Science Tokyo（东京科学大学）
- Institute for Research in Fundamental Sciences (IPM)（伊朗基础科学研究所）
机构由 AI 辅助整理，请以论文原文为准。
AI总结：
本研究通过第一性原理计算发现多种功能化六方MBenes具有超导电性，其中Ti2B2O2的临界温度最高达24 K，且部分超导MBenes展现出非平庸能带拓扑，为拓扑超导研究提供了新平台。
AI中文摘要：
近年来，二维过渡金属硼化物（MBenes）因其在电催化应用中的优异性能而引起了广泛关注。在此，我们通过对原始和表面功能化的六方MBenes进行第一性原理计算，探索其作为新型二维超导体和拓扑材料的潜力。我们对36种化学式为M$_{2}$B$_{2}$和M$_{2}$B$_{2}$T$_{2}$（M = Sc, Ti, V, Zr, Nb, Hf, Ta, Mo, W；T = F, O, OH）的化合物的结构、电子、声子、超导和拓扑性质进行了全面研究。我们的分析确定了21种超导MBenes，其中四种的临界温度（T$_{c}$）超过10 K，其中Ti$_{2}$B$_{2}$O$_{2}$基于McMillan形式预测的最高T$_{c}$为24 K。对于两种最有前景的化合物Ti$_{2}$B$_{2}$O$_{2}$和V$_{2}$B$_{2}$(OH)$_{2}$，我们进一步求解了各向异性的Migdal-Eliashberg方程，获得了零温超导能隙分别为6.1和3.6 meV，以及各向异性T$_{c}$值分别约为32和25 K。基于对称性指标的分析进一步揭示了若干超导MBenes中非平庸的正常态能带拓扑。这些结果表明，在该材料家族中声子介导的超导电性与非平庸的正常态能带拓扑共存，使得MBenes成为未来研究可能出现的拓扑超导电性的有前景平台。
英文摘要：
Recently, two-dimensional transition-metal borides (MBenes) have attracted substantial interest due to their promising properties for electrocatalytic applications. Here, we explore their potential as novel two-dimensional superconductors and topological materials through first-principles calculations on both pristine and surface-functionalized hexagonal MBenes. We conduct a thorough examination of the structural, electronic, phononic, superconducting, and topological properties of 36 compounds with formulas M$_{2}$B$_{2}$ and M$_{2}$B$_{2}$T$_{2}$ (M = Sc, Ti, V, Zr, Nb, Hf, Ta, Mo, W; T = F, O, OH). Our analysis identifies 21 superconducting MBenes, including four with critical temperatures (T$_{c}$) exceeding 10 K, with Ti$_{2}$B$_{2}$O$_{2}$ exhibiting the highest predicted T$_{c}$ of 24 K based on the McMillan formalism. For the two most promising compounds, Ti$_{2}$B$_{2}$O$_{2}$ and V$_{2}$B$_{2}$(OH)$_{2}$, we further solve the anisotropic Migdal-Eliashberg equations, obtaining zero-temperature superconducting gaps of 6.1 and 3.6 meV and anisotropic T$_{c}$ values of approximately 32 and 25 K, respectively. Symmetry-indicator-based analysis further reveals nontrivial normal-state band topology in several superconducting MBenes. These results indicate the coexistence of phonon-mediated superconductivity and nontrivial normal-state band topology within this material family, making MBenes promising platforms for future investigations of the possible emergence of topological superconductivity.
