Static electric field in one-dimensional insulators without boundaries

• Main Authors: Chen, Kuang-Ting (Contributor), Lee, Patrick A. (Contributor)
• Other Authors: Massachusetts Institute of Technology. Department of Physics (Contributor)
• Format: Article
• Language: English
• Published: American Physical Society (APS), 2012-02-17T18:04:37Z.
• Subjects: Article
• Online Access: Get fulltext

In this brief report, we show that in a one-dimensional insulating system with periodic boundary conditions, the coefficient of the θ term in the effective theory is not only determined by the topological index ∫i∑[superscript α]∈[superscript occ]〈u[superscript k]α|∂/∂k|u[superscript kα]〉dk. Specifically, the relative position between the electronic orbitals and the ions also alters the coefficient, as one would expect when one identifies −eθ/2π as the polarization. This resolves a paradox when we apply our previous result to the Su-Shreiffer-Heeger model, where the two ground states related by a lattice translation have θ differed by π. We also show that the static dielectric screening is the same with or without boundaries, in contrast to comments made in our previous paper.
National Science Foundation (U.S.) (Grant No. DMR 1104498)