%0 Journal Article
%T Charge Order from Orbital-dependent Coupling Evidenced by NbSe$_2$
%A Felix Flicker
%A Jasper van Wezel
%J Physics
%D 2015
%I arXiv
%R 10.1038/ncomms8034
%X Niobium diselenide has long served as a prototype of two-dimensional charge ordering, believed to arise from an instability of the electronic structure analogous to the one-dimensional Peierls mechanism. Despite this, various anomalous properties have recently been identified experimentally which cannot be explained by Peierls-like weak-coupling theories. We consider instead a model with strong electron-phonon coupling, taking into account both the full momentum and orbital dependence of the coupling matrix elements. We show that both are necessary for a consistent description of the full range of experimental observations. We argue that NbSe$_2$ is typical in this sense, and that any charge-ordered material in more than one dimension will generically be shaped by the momentum and orbital dependence of its electron-phonon coupling as well as its electronic structure. The consequences will be observable in many charge-ordered materials, including cuprate superconductors.
%U http://arxiv.org/abs/1502.06816v1