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