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arXiv · 2109.05231

Gutzwiller approximation approach to the SU(4) $t$-$J$ model

Jia-Cheng He·Jie Hou·Yan Chen
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Abstract

We develop the Gutzwiller approximation method to obtain the renormalized Hamiltonian of the SU(4) $t$-$J$ model with the corresponding renormalization factors. Subsequently, a mean-field theory is employed on the renormalized Hamiltonian of the model on the honeycomb lattice under the scenario of a cooperative condensation of carriers moving in the resonating valence bond state of flavors. In particular, we find that the extended $s$-wave superconducting state is more favorable than the $d\pm id$-wave superconducting state in the doping range close to quarter filling. The pairing states of the SU(4) case reveal the property that the spin-singlet pairing and the spin-triplet pairing can coexist simultaneously. Our results might provide new insights into the twisted bilayer graphene system.

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Jia-Cheng He, Jie Hou, Yan Chen. 2021-09-11. Gutzwiller approximation approach to the SU(4) $t$-$J$ model. https://doi.org/10.1103/physrevb.105.245117

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