Structure and Electronic State of Boron Atomic Chains on a Noble Metal (111) Surface

Abstract

A two-dimensional crystal of the copper boride was grown on the well-known Cu(111) surface by boron deposition. The atomic structure and the electronic state were analyzed by a concerting usage of positron diffraction and photoemission spectroscopy. The surface layer is composed of the B and Cu atomic chains that are alternately arranged. It has been known that the B and Cu phases are completely separated in three-dimensional (3D) materials. The present study intriguingly revealed that a compound is formed in two-dimension (2D) at the surface. In addition, the Cu(111) substrate was found to affect a relative height between the B and Cu chains. The 2D Cu-B compound on Cu(111) likely becomes an ideal B/Cu interface to develop surface science and boron chemistry.