Exploring the origin of exchange bias and spin glass behavior in 6H hexagonal perovskite structure: Structural and magnetic analysis

Recent research has highlighted the prominence of double perovskites for their diverse properties by incorporating elements across the periodic table. Among them, the hexagonal double perovskite is a subject of growing interest for its potential quantum properties. Our study focuses on the 6H hexagonal double perovskite BaCo[CoRu]O, revealing mixed valence states of Co and Ru ions and notable charge transfer phenomena. By analyzing metal ion Wyckoff positions and considering structural and magnetic properties, we uncover insights into exchange bias mechanisms. Our study underscores the significance of hexagonal perovskite structures in yielding giant exchange bias with appropriate ionic compositions, highlighting the role of rational material design.