Exploring rare-earth based spin frustrated systems

Rare-earth spin frustrated systems featured by strong spin-orbit coupling are distinctly different from their cousins built on 3d magnetic ions in many aspects. Rare-earth ions output a highly anisotropic magnetism which brings many exotic spin phases including quantum spin liquid, and can act as building blocks for a bond-dependent Kitaev spin system. In this talk, I will briefly introduce two rare-earth based spin frustrated families we revealed in recent years. One is the triangular lattice rare-earth chalcogenide ARECh2 (A=alkali or monovalent ions, RE=rare earth, Ch=chalcogen) which appears as a large family of QSL candidates. The other one is van der Waals layered Kitaev spin system REChX (RE=rare earth, Ch=chalcogen, X=halogen). Our studies show that the two families offer an inspiring platform for exploring spin liquid phases, particularly Kitaev physics and its potential applications.