Spin-coupling induced anisotropy swings in ligated Co₂ dimers

Single-molecule magnets with high magnetic anisotropy and easy-axis magnetization are considered to be potential building blocks of quantum computers. While much effort was initially focused on the class of molecules with high total ground-state spin, later studies showed that the molecules with an intrinsic high magnetic anisotropy are more likely to satisfy the requirements for applications as qubits. The theoretical and experimental studies usually focus on the overall magnetization of an SMM. However, in a recent study based on density functional theory, we have demonstrated that the local anisotropy of a ligated Co₂ dimer provides the opportunity for manipulating each spin-carrying center separately [1]. Using the insight obtained from this result we found that both the magnitude and the orientation of magnetization is sensitive to local environment. Moreover, we found an unusual change in the magnetic anisotropy barrier when the spin coupling changes from ferromagnetic to antiferromagnetic. The swings in the magnitude of this barrier were also found to be sensitive to the local symmetry of each center. In this talk I will present the detailed results of this study and will discuss how such features enable quantum switching applications in this molecule.

[1] Z. Hooshmand et al. Physical Review B 2021 (Accepted).