2005/01/31 by S. E. Brown, Stuart E. Brown, Eduardo Fradkin +1 · 1 citation
Materials Science · Physics and Astronomy · #Electronic and Structural Properties of Oxides #Organic and Molecular Conductors Research #Physics of Superconductivity and Magnetism #cond-mat.supr-con
paper · pdf · doi:10.1103/physrevb.71.224512
published as Phys. Rev. B. 71, 224512 (2005) · 9 pages, no figures, 31 references; 1 new figure and minor editing of the text
arxiv created 2005/04/05 · openalex publication_date 2005/06/29 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We study the mean-field theory of charge-density wave (CDW) order in a layered system, including the effect of the long-range Coulomb interaction and of screening by uncondensed electrons. We particularly focus on the conditions necessary for an ``extraordinary'' transition, in which the surface orders at a higher temperature, and is more likely to be commensurate, than the bulk. We interpret recent experiments on Ca_2\ensuremath-xNaxCuO2Cl2 as indicating the presence of commensurate CDW at the surface that is not present in the bulk. More generally, we show that poor screening of the Coulomb interaction tends to stabilize incommensurate order, possibly explaining why the CDW order in La_2\ensuremath-xSrxCuO4 and NbSe2 remains incommensurate to T\ensuremath→0, despite the small magnitude of the incommensurability.