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. Here 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 dxz-dyz orbital order triggered by enhanced on-site Coulomb interaction at the surface. This so-far-overlooked surface-assisted orbital ordering may prevail in transition metal oxides, heavy fermion superconductors and other materials.
Cite
@article{arxiv.1706.09753,
title = {Atomic-scale visualization of surface-assisted orbital order},
author = {Howon Kim and Yasuo Yoshida and Chi-Cheng Lee and Tay-Rong Chang and Horng-Tay Jeng and Hsin Lin and Yoshinori Haga and Zachary Fisk and Yukio Hasegawa},
journal= {arXiv preprint arXiv:1706.09753},
year = {2017}
}
Comments
15 pages, 7 figures