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New interpretation of slave boson mean-field theory of the $t-J$ model: short-range antiferromagnetic and d-wave pairing correlations

Bumsoo Kyung
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Abstract

The $t-J$ Hamiltonian is studied in a mean-field approximation by taking into account antiferromagnetic and d-wave pairing correlations. Considering the presence of antiferromagnetic fluctuations, the weaknesses of a mean-field approximation and the limitation of the $t-J$ model near half-filling, we give a new interpretation to the slave boson mean-field theory of the $t-J$ model. We argue that due to phase coherence-breaking antiferromagnetic fluctuations and quantum fluctuations, superconducting long-range order does not appear strictly in two dimensions. $T_{c}$ resulting from interlayer pairing hopping can lead to a universal relation, when $T_{c}$ is scaled by $T^{max}_{c}$. Systematic reduction of superfluid density and increase of $(Δ_{d})_{max}/K_{B}T_{c}$ ratio below and near optimal doping have their natural explanation in our picture. A crossover temperature $T^{0}$ found in some of magnetic experiments such as NMR is also easily understood in the present framework.

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Bumsoo Kyung. 2000-08-27. New interpretation of slave boson mean-field theory of the $t-J$ model: short-range antiferromagnetic and d-wave pairing correlations. https://arxiv.org/abs/cond-mat/0008384

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