{ "id": "1009.4039", "version": "v2", "published": "2010-09-21T10:12:34.000Z", "updated": "2011-06-18T07:33:09.000Z", "title": "Spectral Properties of Grain Boundaries at Small Angles of Rotation", "authors": [ "Rainer Hempel", "Martin Kohlmann" ], "comment": "22 pages, 3 figures", "journal": "J. Spectr. Theory 1 (2011) 197-219", "doi": "10.4171/JST/9", "categories": [ "math-ph", "math.MP", "math.SP" ], "abstract": "We study some spectral properties of a simple two-dimensional model for small angle defects in crystals and alloys. Starting from a periodic potential $V \\colon \\R^2 \\to \\R$, we let $V_\\theta(x,y) = V(x,y)$ in the right half-plane $\\{x \\ge 0\\}$ and $V_\\theta = V \\circ M_{-\\theta}$ in the left half-plane $\\{x < 0\\}$, where $M_\\theta \\in \\R^{2 \\times 2}$ is the usual matrix describing rotation of the coordinates in $\\R^2$ by an angle $\\theta$. As a main result, it is shown that spectral gaps of the periodic Schr\\\"odinger operator $H_0 = -\\Delta + V$ fill with spectrum of $R_\\theta = -\\Delta + V_\\theta$ as $0 \\ne \\theta \\to 0$. Moreover, we obtain upper and lower bounds for a quantity pertaining to an integrated density of states measure for the surface states.", "revisions": [ { "version": "v2", "updated": "2011-06-18T07:33:09.000Z" } ], "analyses": { "keywords": [ "spectral properties", "grain boundaries", "simple two-dimensional model", "small angle defects", "usual matrix describing rotation" ], "tags": [ "journal article" ], "note": { "typesetting": "TeX", "pages": 22, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2010arXiv1009.4039H" } } }