Yu Liu, Huan Li, Guang-Ming Zhang, L. Yu
The possible heavy fermion superconductivity is carefully examined in the two-dimensional Kondo lattice model with an antiferromagnetic Heisenberg superexchange between local magnetic moments. In order to establish an effective mean field theory in the limit of the paramagnetic heavy Fermi liquid $J_{K}\gg J_{H}$, we find that the spinon or f-fermion singlet pairing from the local antiferromagnetic short-range correlations can reduces the ground state energy substantially. In the presence of the Kondo screening effect, the Cooper pairs between the conduction electrons is induced. Depending on the ratio of the Heisenberg and the Kondo exchange couplings, the resulting superconducting state is characterized by either a d-wave nodal or d-wave nodeless state, and a continuous phase transition exists between these two states.
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http://arxiv.org/abs/1204.1434
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