The AiiDA-KKR plugin and its application to high-throughput impurity embedding into a topological insulator

Abstract

The ever increasing availability of supercomputing resources led computer-based materials science into a new era of high-throughput calculations. Recently, Pizzi et al. introduced the AiiDA framework that provides a way to automate calculations while allowing to store the full provenance of complex workflows in a database. We present the development of the AiiDA-KKR plugin that allows to perform a large number of ab initio impurity embedding calculations based on the relativistic full-potential Korringa-Kohn-Rostoker Green function method. The capabilities of the AiiDA-KKR plugin are demonstrated with the calculation of several thousand impurities embedded into the prototypical topological insulator Sb2Te3. The results are collected in the JuDiT database which we use to investigate chemical trends as well as Fermi level and layer dependence of physical properties of impurities. This includes the study of spin moments, the impurity’s tendency to form in-gap states or its effect on the charge doping of the host-crystal. These properties depend on the detailed electronic structure of the impurity embedded into the host crystal which highlights the need for ab initio calculations in order to get accurate predictions.

The AiiDA-Spirit plugin for automated spin-dynamics simulations and multi-scale modelling based on first-principles calculations

“…In our work, instead of looking for the spin-spiral energies from first-principles calculations, we chose to explore the predictive power of a combination of DFT and LLG calculations for γ-Fe with changing lattice constants. We found a change from the low-spin to high-spin ground state in our DFT results that were performed with the JuKKR code 22 through the AiiDA-KKR plugin 23,24 . This agrees well with earlier DFT calculations where a similar change in the spin moment of the Fe atoms from µ ∼ 1 µ B to > 2.5 µ B is seen 43,44 .…”

“…After the self-consistent DFT calculations, the method of infinitesimal rotations 1 was used to compute the exchange interaction parameters J ij . The series of DFT calculations in this study are orchestrated using the AiiDA-KKR 23 plugins to the AiiDA infrastructure 19 . The complete dataset that includes the full provenance of the calculations is made publicly available in the materials cloud repository 39,40 .…”

“…AiiDA's plugin infrastructure allows to orchestrate and combine different sequences of calculations, possibly using different simulation software and methods, through a common interface. Here, we use this to first generate exchange coupling parameters from DFT calculations using the JuKKR code 22 with the help of the AiiDA-KKR plugin 23,24 . Then, we proceed with spindynamics simulations using the Spirit code 8,18 via the newly developed AiiDA-Spirit plugin 25 .…”

Shared Metadata for Data-Centric Materials Science

“…During the last decade, the interest in workflow development has grown considerably in the scientific community 66 and multi-purpose engines for managing calculation workflows, have been developed, including AFLOW 23,67,68 , AiiDA 31,69 , ASE 34 , and Fireworks 70 . Using these infrastructures, a number of workflows have been used for scientific purposes, like convergence studies 71 , equations of state (e.g., AFLOW Automatic Gibbs Library 72 and the AiiDA common workflows ACWF 73 ) , phonons [74][75][76][77] , elastic properties (e.g., the elastic-properties library for Inorganic Crystalline Compounds of the Materials Project 78 , AFLOW Automatic Elasticity Library, AEL 79 , ElaStic 80 ), anharmonic properties (e.g., the Anharmonic Phonon Library, APL 81 , AFLOW Automatic Anharmonic Phonon Library, AAPL 82 ), highthroughput in the compositional space (e.g., AFLOW Partial Occupation, POCC 83 ), charge transport (e.g., organic semiconductors 84,85 ), of covalent organic frameworks (COFs) for gas storage applications 86 , of spindynamics simulations 87 , high-throughput automated extraction of tight-binding Hamiltionians via Wannier functions 88 , and high-throughput on-surface chemistry 89 There are two types of metadata associated to workflows. Thinking of a workflow as a code to be run, the first type of metadata characterizes the code itself.…”

The AiiDA-KKR plugin and its application to high-throughput impurity embedding into a topological insulator

“…We apply the AiiDA-KKR plugin to embed a large number of impurities into the topological insulator Sb 2 Te 3 . The resulting JuDiT database 41 comes with a webinterface 42 for convenient access to the included data. The following analysis shows some of the physical insights obtained through this study.…”