Stabilizing the magnetic moment of single holmium atoms by symmetry.

Single magnetic atoms, and assemblies of such atoms, on non-magnetic surfaces have recently attracted attention owing to their potential use in high-density magnetic data storage and as a platform for quantum computing. A fundamental problem resulting from their quantum mechanical nature is that the localized magnetic moments of these atoms are easily destabilized by interactions with electrons, nuclear spins and lattice vibrations of the substrate. Even when large magnetic fields are applied to stabilize the magnetic moment, the observed lifetimes remain rather short (less than a microsecond).