论文标题
在TLBISE中探索强大和弱的拓扑状态2
Exploring strong and weak topological states on isostructural substitutions in TlBiSe2
论文作者
论文摘要
拓扑绝缘子（TIS）是独特的材料，其中绝缘式宿主是线性分散的表面状态，该表面状态受到时间反转对称性（TR）的保护。这些状态导致无耗散电流流动，这使得这类材料对自旋应用程序非常有前途。在这里，我们通过使用最先进的基本原理方法，即密度功能理论（DFT）和多体扰动理论（G0W0）结合使用自旋轨道偶联（SOC）来预测新的TI。为此，我们采用众所周知的3D TI，TLBISE2，并在不同地点使用合适的材料进行完整的替代，以检查获得的同生材料是否具有拓扑特性。随后，我们根据SOC诱导的平等反转扫描这些材料（TIME-REVENS NOMMAINT MOVERSA（TRIM））。后来，为了确认所选材料的拓扑性质，我们绘制其表面状态以及Z2不变性的计算。我们的结果表明，Gabise2是强大的拓扑绝缘子（STI）。此外，我们报告了六个弱拓扑绝缘子（WTIS）。 PBBISE2，SNBISE2，SBBISE2，BI2SE2，TLSNSE2和PBSBSE2。我们进一步证明了所有报告的TI都动态稳定，显示了所有真实的振动模式。
Topological Insulators (TIs) are unique materials where insulating bulk hosts linearly dispersing surface states protected by the Time-Reversal Symmetry (TRS). These states lead to dissipationless current flow, which makes this class of materials highly promising for spintronic applications. Here, we predict new TIs via high-throughput screening by employing state-of-the-art first-principles based methodologies, viz., Density Functional Theory (DFT) and many-body perturbation theory (G0W0) combined with Spin-Orbit Coupling (SOC). For this, we take a well-known 3D TI, TlBiSe2 and perform complete substitution with suitable materials at different sites to check if the obtained isostructural materials exhibit topological properties. Subsequently, we scan these materials based on SOC-induced parity inversion at Time-Reversal Invariant Momenta (TRIM). Later, to confirm the topological nature of selected materials, we plot their surface states along with calculation of Z2 invariants. Our results show that GaBiSe2 is a Strong Topological Insulator (STI). Besides, we report six Weak Topological Insulators (WTIs) viz. PbBiSe2, SnBiSe2, SbBiSe2, Bi2Se2, TlSnSe2 and PbSbSe2. We have further verified that all the reported TIs are dynamically stable showing all real phonon modes of vibration.
