Low-energy quantum fluctuations and frustrated magnetism in rare-earth-based Shastry-Sutherland lattices: Insights on the CaCo₂Al₈ structure type antiferromagnets

Studies on magnetic frustration continue to attract much attention in condensed matter physics due to the richness of physics it offers and the unraveling of various exotic ground states of matter driven by magnetic instabilities. In the search for candidate quantum spin-liquid, rare-earth antiferromagnets provide a profitable test field for exploring the various emergent ground states formed when strong magnetic exchange produced by well-defined local magnetic moments compete not only with thermal energy but also with the degree of frustration or symmetry parameter. Here, we explore several CaCo₂Al₈ structure type antiferromagnets and elucidate their strong magnetic frustration-driven ground states occasioned by the arrangements of the magnetic ions on a Shastry-Sutherland lattice and the interplay with quantum fluctuations.