Abstract
The influence of hole doping on magnetic properties is mapped for the compositionally complex high-entropy oxide perovskite . It is found that aliovalent A-site substitution is a viable means to manipulate the magnetically active B-site sublattice. A series of single-crystal films are synthesized and show a general trend toward stronger ferromagnetic response and a shift in magnetic anisotropy as the Sr concentration increases. Magnetometry demonstrates complex and nonuniform responses similar to rigid and uncoupled composites at intermediate dopings. This behavior points to the presence of locally inhomogeneous magnetic phase competition, where ferromagnetic and antiferromagnetic magnetic contributions create a frustrated matrix containing uncompensated spins at the boundaries between these regions. The observations are discussed in the context of known responses to hole doping in the less complex ternary oxides, and they are found to be different from a simple sum of the doped parents. The results are summarized in a preliminary magnetic phase diagram.
| Original language | English |
|---|---|
| Article number | 094204 |
| Journal | Physical Review B |
| Volume | 104 |
| Issue number | 9 |
| DOIs | |
| State | Published - Sep 1 2021 |
Funding
Experiment design, sample synthesis, structural characterization, and computational modeling were supported by the U.S. Department of Energy (DOE), Office of Basic Energy Sciences (BES), Materials Sciences and Engineering Division. B.L.M. thanks the Center for Materials Processing, a Center of Excellence at the University of Tennessee, Knoxville funded by the Tennessee Higher Education Commission (THEC), for financial support. This research used resources of the Advanced Photon Source, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357. Some SQUID magnetometry was performed as a user project at the Center for Nanophase Materials Sciences, which is sponsored at Oak Ridge National Laboratory (ORNL) by the Scientific User Facilities Division, BES, DOE. Some neutron diffraction experiments were conducted at the Spallation Neutron Source, a DOE Office of Science User Facility operated by the Oak Ridge National Laboratory.
| Funders | Funder number |
|---|---|
| U.S. Department of Energy | |
| Office of Science | |
| Basic Energy Sciences | |
| Argonne National Laboratory | DE-AC02-06CH11357 |
| University of Tennessee | |
| Division of Materials Sciences and Engineering | |
| Tennessee Higher Education Commission |