Atomic-scale visualization of surface-assisted orbital order.

ABSTRACT: Orbital-related physics attracts growing interest in condensed matter research, but direct real-space access of the orbital degree of freedom is challenging. We report a first, real-space, imaging of a surface-assisted orbital ordered structure on a cobalt-terminated surface of the well-studied heavy fermion compound CeCoIn₅. Within small tip-sample distances, the cobalt atoms on a cleaved (001) surface take on dumbbell shapes alternatingly aligned in the [100] and [010] directions in scanning tunneling microscopy topographies. First-principles calculations reveal that this structure is a consequence of the staggered d _xz -d _yz orbital order triggered by enhanced on-site Coulomb interaction at the surface. This so far overlooked surface-assist

SUBMITTER: Kim H 

PROVIDER: S-EPMC5609848 | biostudies-literature | 2017 Sep

REPOSITORIES: biostudies-literature