California Institute of Technology, Pasadena, California 91125, USA.
Phys Rev Lett. 2010 Apr 2;104(13):130502. doi: 10.1103/PhysRevLett.104.130502.
We study two a priori unrelated constructions: the spectrum of edge modes in a band topological insulator or superconductor with a physical edge, and the ground state entanglement spectrum in an extended system where an edge is simulated by an entanglement bipartition. We prove an exact relation between the ground state entanglement spectrum of such a system and the spectrum edge modes of the corresponding spectrally flattened Hamiltonian. In particular, we show that gapless edge modes result in degeneracies of the entanglement spectrum.
具有物理边缘的带拓扑绝缘子或超导体的边缘模式谱，以及通过纠缠二分法模拟边缘的扩展系统中的基态纠缠谱。我们证明了这样的系统的基态纠缠谱与相应的谱平坦化哈密顿量的边缘模式谱之间的精确关系。特别地，我们表明无带隙边缘模式导致纠缠谱的简并。
