Many-body generalization of the Z2 topological invariant for the quantum spin Hall effect
Mesoscale and Nanoscale Physics
2008-05-07 v2
Abstract
We propose a many-body generalization of the Z2 topological invariant for the quantum spin Hall insulator, which does not rely on single-particle band structures. The invariant is derived as a topological obstruction that distinguishes topologically distinct many-body ground states on a torus. It is also expressed as a Wilson-loop of the SU(2) Berry gauge field, which is quantized due to the time-reversal symmetry.
Keywords
Cite
@article{arxiv.0708.1639,
title = {Many-body generalization of the Z2 topological invariant for the quantum spin Hall effect},
author = {Sung-Sik Lee and Shinsei Ryu},
journal= {arXiv preprint arXiv:0708.1639},
year = {2008}
}
Comments
4 pages, 3 figures (final version to appear in Phys. Rev. Lett.)