Spectral Densities of Response Functions for the O(3) Symmetric Anderson and Two Channel Kondo Models

Details Spectral Densities of Response Functions for the O(3) Symmetric Anderson and Two Channel Kondo Models Spectral Densities of Response Functions for the O(3) Symmetric Anderson and Two Channel Kondo Models

1999-05-25

arxiv.org/abs/cond-mat/9905361v1

Physics

Condensed Matter

Strongly Correlated Electrons

26 pages, 18 figures, to be published in Eur. Phys. J. B

Scientific paper

10.1007/s100510051181

The O(3) symmetric Anderson model is an example of a system which has a stable low energy marginal Fermi liquid fixed point for a certain choice of parameters. It is also exactly equivalent, in the large U limit, to a localized model which describes the spin degrees of freedom of the linear dispersion two channel Kondo model. We first use an argument based on conformal field theory to establish this precise equivalence with the two channel model. We then use the numerical renormalization group (NRG) approach to calculate both one-electron and two-electron response functions for a range of values of the interaction strength U. We compare the behaviours about the marginal Fermi liquid and Fermi liquid fixed points and interpret the results in terms of a renormalized Majorana fermion picture of the elementary excitations. In the marginal Fermi liquid case the spectral densities of all the Majorana fermion modes display a |omega| dependence on the lowest energy scale, and in addition the zero Majorana mode has a delta function contribution. The weight of this delta function is studied as a function of the interaction U and is found to decrease exponentially with U for large U. Using the equivalence with the two channel Kondo model in the large U limit, we deduce the dynamical spin susceptibility of the two channel Kondo model over the full frequency range. We use renormalized perturbation theory to interpret the results and to calculate the coefficient of the ln omega divergence found in the low frequency behaviour of the T=0 dynamic susceptibility.

Affiliated with

Also associated with

No associations

Rating

Spectral Densities of Response Functions for the O(3) Symmetric Anderson and Two Channel Kondo Models does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Spectral Densities of Response Functions for the O(3) Symmetric Anderson and Two Channel Kondo Models, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Spectral Densities of Response Functions for the O(3) Symmetric Anderson and Two Channel Kondo Models will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-359176