Incommensurate 2k_F charge density wave quantum critical points in two-dimensional metals

We study two-dimensional metals in the vicinity of a quantum critical point, where incommensurate 2k_F charge density wave (CDW) order develops. Starting from a model of two antipodal hot spots at the Fermi surface which are connected by a 2k_F wavevector, we perform a controlled, perturbative renormalization group analysis in the spirit of earlier work by Dalidovich and Lee [1]. We show that the charge density wave transition is indeed continuous and described by a non-Fermi liquid fixed point with a dynamically nested Fermi surface. Our results are potentially relevant to understand the onset of incommensurate CDW order in Cu_xTaS₂ and NbSe₂ at high pressure.

[1] D Dalidovich and S.-S. Lee, Phys. Rev. B 88, 245106 (2013) .