Geometrically protected triple-point crossings in an optical lattice
Abstract
We show how to realize topologically protected crossings of three energy bands, integer-spin analogs of Weyl fermions, in three-dimensional optical lattices. Our proposal only involves ultracold atom techniques that have already been experimentally demonstrated and leads to isolated triple-point crossings (TPCs) which are required to exist by a novel combination of lattice symmetries. The symmetries also allow for a new type of topological object, the type-II, or tilted, TPC. Our Rapid Communication shows that spin-1 Weyl points, which have not yet been observed in the bandstructure of crystals, are within reach of ultracold atom experiments.
Keywords
Cite
@article{arxiv.1711.10935,
title = {Geometrically protected triple-point crossings in an optical lattice},
author = {I. C. Fulga and L. Fallani and M. Burrello},
journal= {arXiv preprint arXiv:1711.10935},
year = {2018}
}
Comments
5 pages, 2 figures + 3 pages, 3 figures supplemental material. Added appendix on model symmetries, fixed typos and added references. This is the final, published version