Abstract by Ethan Gibson
Physics and Astronomy
Antiferromagnetism in High Entropy Oxides
High entropy oxides (HEOs) are materials in which various species of metal cations randomly occupy sites in a crystal lattice and bond to oxygen anions. This work focuses on Mg0.2Ni0.2Co0.2Cu0.2Zn0.2O (MgO-HEO), which is unique among HEOs because it exhibits antiferromagnetic spin order at low temperature. To study the magnetic properties of MgO-HEO, we performed muon spin relaxation (µSR) experiments, revealing information about the internal magnetic field distribution. Initial experimental results suggested that the spin distribution in the sample was random, contradicting earlier reports of an ordered pattern. To resolve this apparent inconsistency, we conducted detailed simulations of the internal magnetic field distribution using the expected antiferromagnetic structure. We found that the simulations could reproduce the experimental data even with an ordered spin arrangement, thus confirming the antiferromagnetism in MgO-HEO.