Peter chaired the ferroelectrics session and gave a contributed talk at the 2018 Conference on Electronic and Advanced Materials this January, in Orlando, FL. His talk was about our recent work on entropy stabilized oxides and disorder dependent effects on magnetic structure. The abstract is provided below, and a big thanks to the American Ceramic Society.
Abstract: Entropy-stabilized materials are stabilized by the configurational entropy of the constituents, rather than the enthalpy of formation of the compound. A unique benefit to entropic stabilization is the increased solubility of elements, which opens a broad compositional space with subsequent local chemical and structural disorder resulting from different atomic sizes and preferred coordinations of the constituents. As the magnetic and electronic properties of oxides are strongly correlated to their chemistry and electronic structure, entropy stabilization could lead to interesting and novel properties. Anisotropic magnetic exchange and the presence of a critical blocking temperature indicates that the entropy-stabilized oxides considered here are antiferromagnetic. Changing the composition of the oxide tunes the disorder and exchange bias and here we exploit this tunability to enhance the strength of the exchange field by a factor of 10x at low temperatures, when compared to a CoO heterostructure. Significant deviations from the rule of mixtures are observed in the structural and magnetic parameters, indicating that the crystal is dominated by configurational entropy. Our results reveal that the unique characteristics of entropy stabilized materials can be utilized to engineer magnetic functional phenomena in oxide thin films.
