Consistent 1/N-expansion for the four-slave-boson approach with an appropriate operator-ordering prescription

Journal Article · Mon May 01 04:00:00 EDT 1995 · Journal of Low Temperature Physics

DOI:https://doi.org/10.1007/BF00752348· OSTI ID:107635

Arrigoni, E ^[1]; Strinati, G ^[2]

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1. Max-Planck-Institut fuer Physik Komplexer Systeme, Stuttgart (Germany)
2. Universita di Roma (Italy)

We study the single-band Hubbard model with arbitrary on-site repulsion U within the four-slave-boson approach. We evaluate 1/N corrections to the mean-field result by properly taking into account the additional terms due to the discretized form of the coherent-state functional integral. We show how the normal-ordering prescription for the bosonic hopping operator z{sub i,{sigma}} introduced by Kotliar and Ruckenstein can be suitably relaxed leading to additional contributions of O(1/N) to physical quantities. The free-particle result at U = 0 is then recovered for arbitrary doping even with the inclusion of fluctuations. Numerical results are shown for finite values of U.

• Sponsoring Organization: USDOE
• OSTI ID: 107635
• Report Number(s): CONF-9409365--
• Journal Information: Journal of Low Temperature Physics, Journal Name: Journal of Low Temperature Physics Journal Issue: 3-4 Vol. 99; ISSN JLTPAC; ISSN 0022-2291
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
BOSONS
ELECTRON CORRELATION
FLUCTUATIONS
HAMILTONIANS
HUBBARD MODEL
SPIN