Instability of the marginal commutative model of tunneling centers interacting with a metallic environment: Role of the electron-hole symmetry breaking

A. Zawadowski, G. Zaránd, P. Nozières, K. Vladár, and G. T. Zimányi
Phys. Rev. B 56, 12947 – Published 15 November 1997
PDFExport Citation

Abstract

The role of the electron-hole symmetry breaking is investigated for a symmetrical commutative two-level system in a metal using the multiplicative renormalization group in a straightforward way. The role of the symmetries of the model and the path-integral technique are also discussed in detail. It is shown that the electron-hole symmetry breaking may make the model non-commutative and generate the assisted tunneling process which is, however, too small itself to drive the system into the vicinity of the two-channel Kondo fixed point. While these results are in qualitative agreement with those of Moustakas and Fisher [Phys. Rev. B 51, 6908 (1995); 53, 4300 (1996)], the scaling equations turn out to be essentially different. We show that the main reason for this difference is that the procedure for the elimination of the high-energy degrees of freedom used by Moustakas and Fisher leaves only the free-energy invariant, however, the couplings generated are not connected to the dynamical properties in a straightforward way and should be interpreted with care. These latter results might have important consequences in other cases where the path-integral technique is used to produce the scaling equations and calculate physical quantities.

  • Received 18 February 1997

DOI:https://doi.org/10.1103/PhysRevB.56.12947

©1997 American Physical Society

Authors & Affiliations

A. Zawadowski and G. Zaránd

  • Institute of Physics, Technical University of Budapest, H 1521 Budafoki út 8., Budapest, Hungary

P. Nozières

  • Institute Laue-Langevin, 38042 Grenoble Cedex, France

K. Vladár

  • Research Institute for Solid State Physics, P.O. Box 49, Budapest, H-1525, Hungary

G. T. Zimányi

  • Physics Department, University of California, Davis, California 95616

References (Subscription Required)

Click to Expand
Issue

Vol. 56, Iss. 20 — 15 November 1997

Reuse & Permissions
Access Options
Author publication services for translation and copyediting assistance advertisement

Authorization Required


×
×

Images

×

Sign up to receive regular email alerts from Physical Review B

Log In

Cancel
×

Search


Article Lookup

Paste a citation or DOI

Enter a citation
×