Spin-bag mechanism of high-temperature superconductivity

A new approach to the theory of high-temperature superconductivity is proposed, based on the two-dimensional antiferromagnetic spin correlations observed in these materials over distances large compared to the lattice spacing. The spin ordering produces an electronic pseudogap Δ_SDW which is locally suppressed by the addition of a hole. This suppression forms a bag inside which the hole is self-consistently trapped. Two holes are attracted by sharing a common bag. The resulting pairing interaction V_k-k' leads to a superconducting energy gap Δ_SC which is nodeless over the Fermi surface, where Δ_{SC~=ΔSDW exp(-t/αU}), with α of order unity.