GENERAL INFORMATION

1. Title of Dataset:
Dataset supporting publication "Fractional Skyrmion tubes in Chiral-Interfaced Three-Dimensional Magnetic Nanowires".


2. Authors:
John Fullerton, Naëmi Leo, Jakub Jurczyk, Claire Donnelly, Dedalo Sanz-Hernández, Luke Skoric, Nicholas Mille, Stefan Stanescu, Donald A MacLaren, Rachid Belkhou, Aurelio Hierro-Rodriguez and Amalio Fernández-Pacheco


3. Date of data collection:
2022-2025.


4. Date of data publication on repository:
2025.


5. Geographic location of data collection:
Vienna (Austria).


6. Information about funding sources that supported the collection of the data (including research project reference/acronym):
This work was supported by the European Community under the Horizon 2020 Program, Contract No. 101001290 (3DNANOMAG), the EPSRC and the Centre for Doctoral Training (CDT) in Photonic Integration and Advanced Data Storage (PIADS), RCUK Grant No. EP/L015323/1.

7. Recommended citation for this dataset:
Same as title.

SHARING/ACCESS/CONTEXT INFORMATION

1. Usage Licenses/restrictions placed on the data (please indicate if different data files have different usage license):
CC-BY (for the data)
MIT (for the code)


2. Links to publications/other research outputs that cite the data:
N/A

3. Links to publications/other research outputs that use the data:
N/A

4. Links to other publicly accessible locations of the data:
N/A

5. Links/relationships to ancillary data sets:
N/A

6. Was data derived from another source? If so, please add link where such work is located:
N/A


DATA & FILE OVERVIEW

1. File List:

This folder contains:


	1) Subfolder "Micromagnetic Simulations", containing Mumax files and scripts that were used to generate the simulated data for the publication as follows:

		I) File "shape.go", this is the modified file employed to compile Mumax3 and have access to a double-helix geometry

		II) File "Double_Helix_Phase_Diagram.mx3", this is an example Mumax3 script used to calculate the energetic phase diagram for Figure 1d of the paper. The script was run multiple times changing the values for Msat, arm_Separation and nm_per_turn_d to varying the saturation magnetization, strand separation and pitch.

		III) Files "Double_Helix_Two_Vortex_State_Hysteresis_Loop.mx3" and "Double_Helix_Two_Vortex_State_Hyst.ovf", these are a Mumax3 script and initial .ovf file for running a hysteresis loop on a double helical nanowire for Figures 2e/f/k of the paper.

		III) Files "Double_Helix_Two_Vortex_State_Minor_Hysteresis_Loop.mx3" and "Double_Helix_Hybrid_Vortex-AP_State_MinorLoop.ovf", these are a Mumax3 script and initial .ovf file for running a minor hysteresis loop on a double helical nanowire from a hybrid vortex-AP states for Figures 3c and supplementary information of the paper.

		V) Files "Double_Helix_Two_Vortex_State_Topological_Charge_Variation.mx3" and "Double_Helix_Two_Vortex_State_TP.ovf", these are a Mumax3 script and initial .ovf file for analyzing the variation in topological charge vs. applied magnetic field for a two vortex state for Figures 4c/d of the paper.

		VI) Files "Double_Helix_Fractional_Skyrmion_State_Topological_Charge_Variation.mx3" and "Double_Helix_Fractional_Skyrmion_State_TP.ovf", these are a Mumax3 script and initial .ovf file for analyzing the variation in topological charge vs. applied magnetic field for a Fractional Skyrmion state for Figures 4e/f/g/h of the paper.


	2) Subfolder "XMCD", containing original ptychographic XMCD images were measured at the HERMES beamline at the SOLEIL synchrotron (beamtime number 20210958, measured beginning of June 2022). The XMCD images saved here were obtained from ptychographic reconstructions with CL and CR light, after image normalisation and alignment (see methods). The XMCD data as *.dat text array and as *.png image, with the field value in the filename. The file [figure_name]_data_list.csv contains seven columns indicating the image index, applied field, date and image number of the original measurement for left- and right-handed circularly polarised light (CL and CR), as well as an annotation in which figures the data is shown.
	It contains four subfolders as follows:

		I) Subfolder "Fig2", contains the XMCD data used for figure 2 in the manuscript. File "Fig2_fitparameters.dat" is a table with amplitudes for Circulation and Polarity for top and bottom helices obtained from linecut fits of images shown in SFig. 4 (see SSec. 1), and is used to plot the experimental hysteresis loops in Fig 2j.

		II) Subfolder "SFig4", contains the XMCD data used for figure 2 in the manuscript and supplementary figure 4.

		III) Subfolder "SFig5-major", contains XMCD data used for figure 3 in the manuscript and supplementary figure 5.

		IV) Subfolder "SFig5-minor", contains XMCD data used for figure 3 in the manuscript and supplementary figure 5 and 6.

		V) Subfolder "SFig9", contains the XMCD data used for supplementary figure 9.

	3) Subfolder "SEM", containing an original SEM image of fabricated double helix structures used for figure 1 in the manuscript.

	4) Subfolder "TEM", containing original TEM images of a representative sample of the FEBID Co nanostructure used for supplementary figure 7.

2. Relationship between files, if important:
N/A


3. Additional related data collected that was not included in the current data package:
N/A


4. Are there multiple versions of the dataset? If so, please indicate where they are located:
N/A


METHODOLOGICAL INFORMATION

1. Description of methods used for collection/generation of data:

Data was generated utilizing the methods described in the main text and methods section of the publication.

2. Methods for processing the data:

Self-developed python/MATLAB code and Paraview for analysing/visualizing the simulations.
The XMCD image *.dat files can be loaded, e.g., using the functions numpy.loadtxt() or imread from matplotlib.pyplot.imread().
The TEM image .dm3 files can be loaded by ImageJ or digital micrograph.


3. Instrument- or software-specific information needed to interpret/reproduce the data, please indicate their location:

Paraview: https://www.paraview.org
Imagej: https://imagej.net/software/fiji/

4. Standards and calibration information, if appropriate:
N/A

5. Environmental/experimental conditions:
N/A

6. Describe any quality-assurance procedures performed on the data:
N/A

7. People involved with sample collection, processing, analysis and/or submission, please specify using CREDIT roles
All authors contributed to this work.

8. Author contact information:
Amalio Fernández-Pacheco: <amalio.fernandez-pacheco@tuwien.ac.at>
John Fullerton: <jfullerton@anl.gov>
Naëmi Leo: <n.leo@lboro.ac.uk>

