Nonmagnetic impurity perturbation to the quasi-two-dimensional quantum helimagnet LiCu2O2

A complete phase diagram of Zn-substituted quantum quasi-two-dimensional helimagnet LiCu2O2 has been presented. Helical ordering transition temperature (Th) of the original LiCu2O2 follows finite size scaling for less than ∼5.5% Zn substitution, which implies the existence of finite helimagnetic domains with domain boundaries formed with nearly isolated spins. Higher Zn substitution ≥5.5% quenches the long-range helical ordering and introduces …