Numerical Renormalization Group computation of temperature dependent specific heat for a two-channel Anderson model

被引:4
作者
Ferreira, J. V. B. [1 ]
Ferreira, A. I. I. [1 ]
Leite, A. H. [1 ]
Libero, V. L. [1 ]
机构
[1] Univ Estadual Sao Paulo, Inst Fis Sao Carlos, Sao Paulo, Brazil
关键词
Multi-channel Anderson model; Local moment in compound and alloy; Kondo effect; Numerical Renormalization Group; Heavy fermion; Specific heat; Theories and models of many electron systems; TRANSFORMATION;
D O I
10.1016/j.jmmm.2011.10.013
中图分类号
T [工业技术];
学科分类号
08 ;
摘要
The Numerical Renormalization Group (NRG) is applied to diagonalize a two-channel Anderson model describing a local magnetic impurity embedded in a fermionic bath. In spite of the difficulty in computing the specific heat using NRG, the interleaving discretization and multi-step iterative transformation virtually eliminate the numerical oscillations introduced by the logarithmic discretization of the conduction band. These allow to cover uniformly a large range of temperature, from the top of the band to a very small fraction of the bandwidth. This is relevant in describing, for instance, the presence of a low temperature Kondo resonance together with a high temperature Schottky peak, as well to cover Fermi and non-Fermi liquid regimes, like in the recent studied Ce1-xLaxNi9Ge4 family. We highlight the importance in describing the Schottky peak to define the number of degrees of freedom of the local levels, in order to correctly define the model to describe a given compound. (C) 2011 Elsevier B.V. All rights reserved.
引用
收藏
页码:1011 / 1016
页数:6
相关论文
共 19 条
[1]   Can competition between the crystal field and the Kondo effect cause non-fermi-liquid-like behavior? [J].
Anders, FB ;
Pruschke, T .
PHYSICAL REVIEW LETTERS, 2006, 96 (08) :1-4
[2]   Numerical renormalization group method for quantum impurity systems [J].
Bulla, Ralf ;
Costi, Theo A. ;
Pruschke, Thomas .
REVIEWS OF MODERN PHYSICS, 2008, 80 (02) :395-450
[3]   Numerical renormalization-group computation of specific heats [J].
Costa, SC ;
Paula, CA ;
Libero, VL ;
Oliveira, LN .
PHYSICAL REVIEW B, 1997, 55 (01) :30-33
[4]   TRANSPORT-COEFFICIENTS OF THE ANDERSON MODEL VIA THE NUMERICAL RENORMALIZATION-GROUP [J].
COSTI, TA ;
HEWSON, AC ;
ZLATIC, V .
JOURNAL OF PHYSICS-CONDENSED MATTER, 1994, 6 (13) :2519-2558
[5]   Exotic Kondo effects in metals: magnetic ions in a crystalline electric field and tunnelling centres [J].
Cox, DL ;
Zawadowski, A .
ADVANCES IN PHYSICS, 1998, 47 (05) :599-942
[6]   Heat capacity of Ce1-xLaxCu4Al Kondo alloys [J].
Falkowski, M. ;
Kowalczyk, A. ;
Tolinski, T. .
JOURNAL OF ALLOYS AND COMPOUNDS, 2011, 509 (21) :6135-6138
[7]   Multi-step transformation in numerical renormalization group [J].
Ferreira, Joao V. B. ;
Libero, Valter L. ;
Oliveira, Luiz N. .
COMPUTER PHYSICS COMMUNICATIONS, 2006, 174 (11) :862-868
[8]   Non-Fermi liquid fixed points of a two-channel Anderson model [J].
Ferreira, JVB ;
de Oliveira, LN ;
Cox, DL ;
Líbero, VL .
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS, 2001, 226 :196-198
[9]   Magnetic susceptibility of a two-channel Anderson model [J].
Ferreira, JVB ;
de Oliveira, LN ;
Cox, DL ;
Líbero, VL .
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS, 2001, 226 :132-133
[10]   Theory of the Anderson impurity model: The Schrieffer-Wolff transformation reexamined [J].
Kehrein, SK ;
Mielke, A .
ANNALS OF PHYSICS, 1996, 252 (01) :1-32