Nanoscale Noncollinear Spin Textures in Thin Films of a D2d Heusler Compound

Magnetic nano-objects, namely antiskyrmions and Bloch skyrmions, have been found to coexist in single-crystalline lamellae formed from bulk crystals of inverse tetragonal Heusler compounds with D2d symmetry. *

Skyrmions can be observed in real-space by various direct imaging techniques. *

In the article “Nanoscale Noncollinear Spin Textures in Thin Films of a D2d Heusler Compound”  Ankit K. Sharma, Jagannath Jena, Kumari Gaurav Rana, Anastasios Markou, Holger L. Meyerheim, Katayoon Mohseni, Abhay K. Srivastava, Ilya Kostanoskiy, Claudia Felser and Stuart S. P. Parkin  describe the use of magnetic force microscopy (MFM) imaging to investigate magnetic textures in epitaxial thin films of [001]-oriented Mn2RhSn formed by magnetron sputtering.*

They find evidence for magnetic nano-objects which exhibit a wide range of sizes with stability with respect to magnetic field and temperature that is similar to single-crystalline lamellae. *

However, the nano-objects do not form well-defined arrays, nor is any evidence found for helical spin textures. This is speculated to likely be a consequence of the poorer homogeneity of chemical ordering in the thin films. *

Evidence is found for elliptically distorted nano-objects along perpendicular crystallographic directions within the epitaxial films, which is consistent with elliptical Bloch skyrmions observed in single-crystalline lamellae. Thus, these measurements provide strong evidence for the formation of noncollinear spin textures in thin films of Mn2RhSn. *

Using these films, it is shown that individual nano-objects can be deleted using a local magnetic field from a magnetic AFM tip and collections of nano-objects can be similarly written. *

For writing and deleting the nano-objects, magnetic AFM probes from NanoWorld of the Pointprobe® MFMR type were used. *

These observations described in the article suggest a path toward the use of these nano-objects in thin films with D2d symmetry as magnetic memory elements paving the way to the realization of skyrmionic devices based on Heusler thin films. *

Figure 5 from Ankit K. Sharma et al. Nanoscale Noncollinear Spin Textures in Thin Films of a D2d Heusler Compound : Controlled creation and annihilation of nano-objects in a 35 nm-thick Mn2RhSn thin film. a) Schematic illustration of magnetization orientations of MFM tip and sample for writing. The distance between tip and the sample is the scan height z. b–e) MFM images in zero field and z = 80, 40, 30, and 20 nm, respectively at 200 K. f) Contact-mode image in zero field and 200 K. The blue and red colors represent up and down magnetization, respectively. Images in (b)–(f) are at the same scale: a scale bar is given in (f). g–i) MFM images taken at z = 70, 50, and 30 nm at 100 K under Hz = 180 mT. Images in (g)–(i) are at the same scale: a scale bar is given in (i). For writing and deleting the nano-objects, magnetic AFM probes from NanoWorld of the Pointprobe® MFMR type were used.
Figure 5 from Ankit K. Sharma et al. Nanoscale Noncollinear Spin Textures in Thin Films of a D2d Heusler Compound :
Controlled creation and annihilation of nano-objects in a 35 nm-thick Mn2RhSn thin film. a) Schematic illustration of magnetization orientations of MFM tip and sample for writing. The distance between tip and the sample is the scan height z. b–e) MFM images in zero field and z = 80, 40, 30, and 20 nm, respectively at 200 K. f) Contact-mode image in zero field and 200 K. The blue and red colors represent up and down magnetization, respectively. Images in (b)–(f) are at the same scale: a scale bar is given in (f). g–i) MFM images taken at z = 70, 50, and 30 nm at 100 K under Hz = 180 mT. Images in (g)–(i) are at the same scale: a scale bar is given in (i).

*Ankit K. Sharma, Jagannath Jena, Kumari Gaurav Rana, Anastasios Markou, Holger L. Meyerheim, Katayoon Mohseni, Abhay K. Srivastava, Ilya Kostanoskiy, Claudia Felser, Stuart S. P. Parkin
Nanoscale Noncollinear Spin Textures in Thin Films of a D2d Heusler Compound
Advanced Materials, Volume 33, Issue 32, August 12, 2021, 2101323
DOI: https://doi.org/10.1002/adma.202101323

Open Access The article “Nanoscale Noncollinear Spin Textures in Thin Films of a D2d Heusler Compound” Ankit K. Sharma, Jagannath Jena, Kumari Gaurav Rana, Anastasios Markou, Holger L. Meyerheim, Katayoon Mohseni, Abhay K. Srivastava, Ilya Kostanoskiy, Claudia Felser and Stuart S. P. Parkin is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.