Agenda

Résumé : Lanthanide rare-earth magnetic materials, particularly those Yb3+-based magnets, have attracted significant interest as potential candidates hosting Kitaev exchange in honeycomb lattices. Recently, Yb2Si2O7 has been reported as a new quantum dimer magnet (QDM) with a gapped singlet ground state at zero field [G. Hester et. al, Phys. Rev. Lett., 123, 027201, (2019)]. However, the fundamental question remains what the microscopic origin is for the anisotropic exchange interactions, which is essentially related to the observed macroscopic ground state and excitations. We present an ab−initio investigation utilising an advanced multi-reference configuration methodology to determine the origin and nature of the anisotropy. Our results provide microscopic insights into the spin-orbit coupling effect in the system.