Dynamical impurity problems
Abstract
In the past few years there has been a resurgence of interest in dynamical impurity problems, as a result of developments in the theory of correlated electron systems. The general dynamical impurity problem is a set of conduction electrons interacting with an impurity which has internal degrees of freedom. The simplest and earliest example, the Kondo problem, has attracted interest since the midsixties not only because of its physical importance but also as an example of a model displaying logarithmic divergences order by order in perturbation theory. It provided one of the earliest applications of the renormalization group method, which is designed to deal with just such a situation. As we shall see, the antiferromagnetic Kondo model is controlled by a strongcoupling fixed point, and the essence of the renormalization group solution is to carry out the global renormalization numerically starting from the original (weakcoupling) Hamiltonian. In these lectures, we shall describe an alternative route in which we identify an exactly solvable model which renormalizes to the same fixed point as the original dynamical impurity problem. This approach is akin to determining the critical behavior at a second order phase transition point by solving any model in a given universalitymore »
 Authors:
 Brookhaven National Lab., Upton, NY (United States)
 California Univ., Los Angeles, CA (United States). Dept. of Physics
 Publication Date:
 Research Org.:
 Brookhaven National Lab., Upton, NY (United States)
 Sponsoring Org.:
 USDOE, Washington, DC (United States); National Science Foundation, Washington, DC (United States)
 OSTI Identifier:
 10157485
 Report Number(s):
 BNL60297; CONF93063381
ON: DE94013025; CNN: Grant DMR9312606; TRN: 94:012934
 DOE Contract Number:
 AC0276CH00016
 Resource Type:
 Conference
 Resource Relation:
 Conference: 1993 international summer school on fundamental problems in statistical mechanics,Altenberg (Germany),27 Jun  10 Jul 1993; Other Information: PBD: [1993]
 Country of Publication:
 United States
 Language:
 English
 Subject:
 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ELECTRON CORRELATION; IMPURITIES; HIGHTC SUPERCONDUCTORS; HAMILTONIANS; KONDO EFFECT; CORRELATION FUNCTIONS; PHASE TRANSFORMATIONS; 665411; BASIC SUPERCONDUCTIVITY STUDIES
Citation Formats
Emery, V.J., and Kivelson, S.A. Dynamical impurity problems. United States: N. p., 1993.
Web.
Emery, V.J., & Kivelson, S.A. Dynamical impurity problems. United States.
Emery, V.J., and Kivelson, S.A. 1993.
"Dynamical impurity problems". United States.
doi:. https://www.osti.gov/servlets/purl/10157485.
@article{osti_10157485,
title = {Dynamical impurity problems},
author = {Emery, V.J. and Kivelson, S.A.},
abstractNote = {In the past few years there has been a resurgence of interest in dynamical impurity problems, as a result of developments in the theory of correlated electron systems. The general dynamical impurity problem is a set of conduction electrons interacting with an impurity which has internal degrees of freedom. The simplest and earliest example, the Kondo problem, has attracted interest since the midsixties not only because of its physical importance but also as an example of a model displaying logarithmic divergences order by order in perturbation theory. It provided one of the earliest applications of the renormalization group method, which is designed to deal with just such a situation. As we shall see, the antiferromagnetic Kondo model is controlled by a strongcoupling fixed point, and the essence of the renormalization group solution is to carry out the global renormalization numerically starting from the original (weakcoupling) Hamiltonian. In these lectures, we shall describe an alternative route in which we identify an exactly solvable model which renormalizes to the same fixed point as the original dynamical impurity problem. This approach is akin to determining the critical behavior at a second order phase transition point by solving any model in a given universality class.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = 1993,
month =
}

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