FUNCTIONAL-INTEGRAL FORMULATION OF THE SLAVE-BOSON APPROACH - BEYOND THE MEAN-FIELD TREATMENT WITH THE CORRECT CONTINUUM-LIMIT

被引：30

作者：

ARRIGONI, E ^{[1
]}

CASTELLANI, C ^{[1
]}

GRILLI, M ^{[1
]}

RAIMONDI, R ^{[1
]}

STRINATI, GC ^{[1
]}

机构：

[1] UNIV ROMA LA SAPIENZA,DIPARTIMENTO FIS,I-00185 ROME,ITALY

来源：

PHYSICS REPORTS-REVIEW SECTION OF PHYSICS LETTERS | 1994年 / 241卷 / 06期

基金：

美国国家科学基金会;

关键词：

D O I：

10.1016/0370-1573(94)00051-4

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

We consider the widely adopted slave-boson method, which relies on a coherent-state functional-integral representation of the partition function and illustrate how to deal with the continuum imaginary time limit required by the very definition of the functional integral. We show that a correct treatment of the continuum limit of the functional integral modifies the free energy when fluctuation (1/N) corrections beyond the mean-field solution are considered. For the sake of definiteness, we consider a model Hamiltonian with an infinite (on-site) Hubbard repulsion. Numerical results are further presented for a two-level single-site model system. The additional terms in the free energy resulting from considering the correct continuum limit are shown to validate the 1/N expansion and to be consistent with relating the fluctuation results obtained via the ''radial'' and ''Cartesian'' gauges. Our analysis calls for a revision of several outcomes of the slave-boson method with the inclusion of fluctuation corrections.

引用

页码：291 / 369

页数：79

共 22 条

[11]

Gradshteyn I.S., 1965, TABLES OF INTEGRALS

[12] 1/N EXPANSION FOR THE TRANSPORT-COEFFICIENTS OF THE SINGLE-IMPURITY ANDERSON MODEL [J].

HOUGHTON, A ;

READ, N ;

WON, H .

PHYSICAL REVIEW B, 1987, 35 (10) :5123-5150

[13] NEW FUNCTIONAL INTEGRAL APPROACH TO STRONGLY CORRELATED FERMI SYSTEMS - THE GUTZWILLER APPROXIMATION AS A SADDLE-POINT [J].

KOTLIAR, G ;

RUCKENSTEIN, AE .

PHYSICAL REVIEW LETTERS, 1986, 57 (11) :1362-1365

[14] FERMI-LIQUID DESCRIPTION OF LA2-XSRCUO4 [J].

KOTLIAR, G ;

LEE, PA ;

READ, N .

PHYSICA C, 1988, 153 :538-542

[15] LARGE-ORBITAL-DEGENERACY EXPANSION FOR THE LATTICE ANDERSON MODEL [J].

MILLIS, AJ ;

LEE, PA .

PHYSICAL REVIEW B, 1987, 35 (07) :3394-3414

[16]

Popov V. N., 1983, FUNCTIONAL INTEGRALS

[17] ROLE OF INFRARED DIVERGENCES IN THE 1/N EXPANSION OF THE U = INFINITY ANDERSON MODEL [J].

READ, N .

JOURNAL OF PHYSICS C-SOLID STATE PHYSICS, 1985, 18 (13) :2651-2665

[18] ON THE SOLUTION OF THE COQBLIN-SCHRIEFFER HAMILTONIAN BY THE LARGE-N EXPANSION TECHNIQUE [J].

READ, N ;

NEWNS, DM .

JOURNAL OF PHYSICS C-SOLID STATE PHYSICS, 1983, 16 (17) :3273-3295

[19]

Rickayzen G., 1980, GREENS FUNCTIONS CON

[20]

SCHULMAN LS, 1981, TECHNIQUES APPLICATI

← 1 2 3 →