Magnetic skyrmions have been the focus of intense research due to their unique qualities which result from their topological protections. Previous work on ${\mathrm{Cu}}_2{\mathrm{OSeO}}_3$, the only known insulating multiferroic skyrmion material, has shown that chemical substitution alters the skyrmion phase. We chemically substitute Zn, Ag, and S into powdered ${\mathrm{Cu}}_2{\mathrm{OSeO}}_3$ to study the effect on the magnetic phase diagram. In both the Ag and the S substitutions, we find that the skyrmion phase is stabilized over a larger temperature range, as determined via magnetometry and small-angle neutron scattering (SANS). Meanwhile, while previous magnetometry characterization suggests two high temperature skyrmion phases in the Zn-substituted sample, SANS reveals the high temperature phase to be skyrmionic while we are unable to distinguish the other from helical order. Overall, chemical substitution weakens helical and skyrmion order as inferred from neutron scattering of the $\left|q\right|\approx 0.01{\text{Å}}^{-1}$ magnetic peak.

• Received 10 September 2019
• Revised 20 August 2020
• Accepted 22 September 2020

DOI:https://doi.org/10.1103/PhysRevB.102.134410