Download or read book Cellular Dynamical Mean Field Theory of the Holstein Polaron Problem written by Jean-Marc ROBIN and published by Lulu.com. This book was released on 2010-03-29 with total page 54 pages. Available in PDF, EPUB and Kindle. Book excerpt: We show how to set up a Cellular Dynamical Mean Field Theory for the Holstein's polaron problem using the exact solution of a cluster of n sites embedded in a Weiss's field. We show that a restricted basis, that allows excitations of phonons only for n sites at a time, reproduces exactly the equations of the n-site Dynamical Mean Field Theory, and enables to check the proposed decoupling scheme of the Green's functions via Exact Numerical Diagonalizations. We introduce a real space formulation of the Cellular Dynamical Mean Field Theory that applies to any lattice with or without periodic boundary conditions and that allows to partition the lattice into different kinds of clusters.