Discovery of the First Topological Kondo Insulator: Samarium Hexaboride
Year: 2012
Type: preprint
Abstract: One of the most important new concepts in modern condensed matter physics is that there are new states of matter where the bulk is an unusual insulator in that it has topologically-protected metallic states on the surface. Meanwhile, in the seemingly unrelated system of strongly correlated insulators known as Kondo insulators, longstanding puzzles have remained unanswered for over thirty years. In particular, it has been found that some Kondo insulators display strange electrical transport that cannot be understood if one assumes that it is governed by the three-dimensional (3D) bulk. Here we study the transport properties of the Kondo insulator SmB6 with a novel configuration designed to distinguish bulk-dominated conduction from surfacedominated conduction. We find that this material is a true topological insulator with a metallic surface and a fully insulating bulk, which means that its surface states can be easily studied. Thus SmB6 is destined to be a very important material for researching the properties of topologically-protected surface states, and the discovery of the metallic surface also resolves the last remaining puzzles about the strange transport behavior of this material.
Source: arXiv (Cornell University)
Language: English
Subfield: Condensed Matter Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2782989897