Dataset for "Nanoscale Confinement of Skyrmions in FeGe Device shapes"

Dataset for "Confinement of Skyrmions in Nanoscale FeGe Device Structures"

This dataset comprises of the data from the simulation part of the study of the paper "Confinement of Skyrmions in Nanoscale FeGe Device Structures." In this study, a series of five FeGe nanostructures were milled by Focused Ion Beam (FIB) lithography, into two 'blocks' and three 'dumbbells' in order to investigate the formation of skyrmions around a geometric constriction. The experimental samples were imaged by way of Lorentz Transmission Electron Microscopy (LTEM). Simulations were then performed in order to help understand the physics of skyrmion formation within these samples.

Prerequisites

In order to run the scripts contained in the subfolders, the following are needed:

• An installation of MuMax 3.10 (https://mumax.github.io/download.html). In order to set this up, you must first install the NVidia graphics drivers appropriate to your system, and the CUDA libraries.
• Python > 3.6
• A number of Python dependencies which are specified in the requirements.txt file in the root directory. Once Python is installed, we recommend installing these via a virtualenv:

virtualenv env
source env/bin/activate
python -m pip install -r requirements.txt

Dataset Details

This dataset consists of the following tar.xz archives:

• preprocessing.tar.xz - A small preprocessing library and script for converting experimental TEM images into a 'mask' that can be used for forming a simulation mesh. To run these, run the following command:

tar xf preprocessing.tar.xz
cd preprocessing
python generate-masks.py

• simulation-scripts.tar.xz - This contains five folders labelled B1, B2 and D1, D2 and D3 representing the five different sample types. In each folder is the MuMax simulation script used for this study, along with the cropped final mask image which is used in the simulation script. To rerun each part of the study (please note that the run time is several weeks per script on current hardware), for e.g. for the B1 sample you can do the following:

tar xf simulation-scripts.tar.xz
cd simulation-scripts/B1/
mumax3 B1.mx3

• B1.tar.xz, B2.tar.xz, D1.tar.xz, D2.tar.xz, D3.tar.xz - These archives contain the simulation results for each of the five samples in OVF format. They can be extracted into the simulation-scripts folder to allow the postprocessing analysis to be repeated.
• postprocessing.tar.xz - This archive contains a postprocessing script which calculates the projection of the magnetisation in the z-direction from the simulation output data. To run this, run the simulations, or download the results archives and place the extracted files into the simulation-scripts folder and then run:

tar xf postprocessing.tar.xz
cd postprocessing
python postprocess.py