期刊
NUCLEAR PHYSICS B
卷 594, 期 3, 页码 769-789出版社
ELSEVIER SCIENCE BV
DOI: 10.1016/S0550-3213(00)00657-X
关键词
strongly correlated electrons; field theories; non-perturbative methods
We introduce a new path integral representation for slave bosons in the radial gauge which is valid beyond the conventional fluctuation corrections to a mean-field solution. For electronic lattice models, defined on the constrained Fock space with no double occupancy, all phase fluctuations of the slave particles can be gauged away if the Lagrange multipliers which enforce the constraint on each lattice site are promoted to time-dependent fields. Consequently, only the amplitude (radial part) of the slave boson fields survives. It has the special property that it is equal to its square in the physical subspace. This renders the functional integral for the radial field Gaussian, even when nonlocal Coulomb-type interactions are included. We propose (i) a continuum integral representation for the set-up of further approximation schemes, and (ii) a discrete representation with an Ising-like radial variable, valid for long-ranged interactions as well. The latter scheme can be taken as a starting point for numerical evaluations. (C) 2001 Elsevier Science B.V. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据