Spatial distribution of substitutional Mn-As clusters in ferromagnetic (Zn,Sn,Mn)As 2 thin films revealed by image reconstruction of atom probe tomography data

Oomae H., Shinoda M., Asubar J. T., Sato K., Toyota H., Mayama N., ...More

Journal of Applied Physics, vol.125, no.7, 2019 (SCI-Expanded, Scopus) identifier identifier

  • Publication Type: Article / Article
  • Volume: 125 Issue: 7
  • Publication Date: 2019
  • Doi Number: 10.1063/1.5070074
  • Journal Name: Journal of Applied Physics
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Open Archive Collection: Article
  • Azerbaijan State University of Economics (UNEC) Affiliated: Yes

Abstract

The ferromagnetic transition in (Zn,Sn,Mn)As 2 thin films is explained in terms of magnetic percolation in a Mn-As clustering network. We first studied the relationship between the spatial distribution of Mn-As clusters and the Curie temperature (T C ). The local atomic structure was reconstructed from datasets of atomic positions in (Zn,Sn,Mn)As 2 obtained by atom probe tomography (APT). To probe the local atomic structure and the magnetic properties of Mn-As clusters in ZnSnAs 2 thin films, we investigated molecular beam epitaxially grown (Zn,Sn,Mn)As 2 samples doped with 2.1 and 3.6 at. % Mn. Representative regions with a low and high Mn concentration were extracted from APT datasets. Mn-As clusters containing 2-36 Mn atoms were identified in regions of high Mn concentration. We also obtained a correlation between T C and Mn-As clustering that was consistent with not only the experimental results but also first-principles calculations using the mean-field approximation.