Location of Repository

Anderson Orthogonality (AO) refers to the fact that the ground states of two Fermi seas that experience different local scattering potentials, say |G_I> and |G_F>, become orthogonal in the thermodynamic limit of large particle number N, in that |<G_I|G_F>| ~ N^(- Delta_AO^2 /2) for N->infinity. We show that the numerical renormalization group (NRG) offers a simple and precise way to calculate the exponent Delta_AO: the overlap, calculated as function of Wilson chain length k, decays exponentially, ~ exp(-k alpha), and Delta_AO can be extracted directly from the exponent alpha. The results for Delta_AO so obtained are consistent (with relative errors typically smaller than 1%) with two other related quantities that compare how ground state properties change upon switching from |G_I> to |G_F>: the difference in scattering phase shifts at the Fermi energy, and the displaced charge flowing in from infinity. We illustrate this for several nontrivial interacting models, including systems that exhibit population switching.Comment: 10 pages, 7 figure

Topics:
Condensed Matter - Strongly Correlated Electrons, Condensed Matter - Mesoscale and Nanoscale Physics

Year: 2011

DOI identifier: 10.1103/PhysRevB.84.075137

OAI identifier:
oai:arXiv.org:1104.3058

Provided by:
arXiv.org e-Print Archive

Download PDF:To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.