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Chiral d+is superconducting state in the two dimensional t-t' Hubbard model

J. Mraz·R. Hlubina
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Abstract

Applying the recently developed variational approach to Kohn-Luttinger superconductivity to the t-t' Hubbard model in two dimensions, we have found, for sizeable next-nearest neighbor hopping, an electron density controlled quantum phase transition between a d-wave superconducting state close to half filling and an s-wave superconductor at lower electron density. The transition occurs via an intermediate time reversal breaking d+is superconducting phase, which is characterized by nonvanishing chirality and density-current correlation. Our results suggest the possibility of a bulk time reversal symmetry breaking state in overdoped cuprates.

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J. Mraz, R. Hlubina. 2003-09-08. Chiral d+is superconducting state in the two dimensional t-t' Hubbard model. https://doi.org/10.1103/physrevb.69.104501

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