Structural and magnetic properties of Fe-doped Pt3Sn, a potential magnetic Weyl semimetal candidate

The magnetic doping of Dirac semimetals to create Weyl semimetals through broken time-reversal symmetry is a very interesting and useful way to access the exotic transport properties of the Weyl phase while also having the ability to exert a degree of control over physical properties for device applications. Work in this area thus far has been restricted to Cd3As2, but recent work on the material Pt3Sn has experimentally demonstrated its viability in this area as well, although the effect was only observed at temperatures <25 K. In this work, we take a step toward accessing the Weyl semimetal phase of Pt3Sn at higher temperatures by observing changes to physical properties that occur with increased Fe concentration. We find a very high solubility of Fe within the Pt3Sn lattice, remarkable resiliency of the structure to non-stoichiometric compositions, and strong room-temperature ferromagnetism across a broad range of compositions. Previous theoretical calculations combined with the solubility of magnetic dopants in the Pt3Sn matrix demonstrated in this work offer an encouraging result that the system may be a candidate for observing a magnetically doped Weyl semimetal phase at higher temperatures in the future, while also suggesting the usefulness of the Pt3X structure more generally, as many elements are stable on the X site and thus should be usable to access many other physical properties.