Npj Comput. Mater.: 二维材料量子点缺陷—建了数据库
点缺陷普遍存在，对晶体材料的物理特性有着重要影响。在过去的十年中，原子级薄二维晶体由于其本身独特的、易于调控的物理性质，成为了一类很有前景的材料。与块状材料中的内部深缺陷相比，二维材料中的缺陷更接近表面，这使得它们更容易创建、操作和表征。这些特性使它们成为量子缺陷的理想宿主系统。基于密度泛函理论的第一性原理计算可以详细研究点缺陷的物理和化学特性，以及它们是如何影响材料的结构、电子和光学特性的。然而，缺陷计算的复杂性涉及巨大的超胞、局部磁矩、静电校正等，这让很多科学界难以处理。
该文近期发表于npj Computational Materials 8：56 (2022)，英文标题与摘要如下，点击左下角“阅读原文”可以自由获取论文PDF。
Atomically thin two-dimensional (2D) materials are ideal host systems for quantum defects as they offer easier characterisation, manipulation and read-out of defect states as compared to bulk defects. Here we introduce the Quantum Point Defect (QPOD) database with more than 1900 defect systems comprising various charge states of 503 intrinsic point defects (vacancies and antisites) in 82 different 2D semiconductors and insulators. The Atomic Simulation Recipes (ASR) workflow framework was used to perform density functional theory (DFT) calculations of defect formation energies, charge transition levels, Fermi level positions, equilibrium defect and carrier concentrations, transition dipole moments, hyperfine coupling, and zero-field splitting. Excited states and photoluminescence spectra were calculated for selected high-spin defects. In this paper we describe the calculations and workflow behind the QPOD database, present an overview of its content, and discuss some general trends and correlations in the data. We analyse the degree of defect tolerance as well as intrinsic dopability of the host materials and identify promising defects for quantum technological applications. The database is freely available and can be browsed via a web-app interlinked with the Computational 2D Materials Database (C2DB).
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