2003/04/30 by Brijesh Kumar, B. Sriram Shastry · 10 citations
Materials Science · Physics and Astronomy · #Advanced Condensed Matter Physics #Magnetic and transport properties of perovskites and related materials #Physics of Superconductivity and Magnetism #cond-mat.str-el #cond-mat.supr-con
paper · pdf · doi:10.1103/physrevb.68.104508
published as Phys. Rev. B 68, 104508 (2003) · Published in Physical Review B, total 1 tex + 9 eps files. Erratum added as separate tex file on November 7, 2003, a numerical factor corrected in the erratum on Dec 3, 2003
openalex publication_date 2003/09/11 · arxiv created 2003/12/03 · arxiv updated 2009/11/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
Motivated by the recent discovery of superconductivity in two-dimensional CoO2 layers, we present some possibly useful results of the resonating valence bond mean-field theory applied to the triangular lattice. An interesting time reversal breaking superconducting state arises from strongly frustrated interactions. Away from half filling, the order parameter is found to be complex, and yields a fully gapped quasiparticle spectrum. The sign of the hopping plays a crucial role in the analysis, and we find that superconductivity is as fragile for one sign as it is robust for the other. NaxCoO2\ensuremath⋅yH2O is argued to belong to the robust case, by comparing the local-density approximation fermi surface with an effective tight-binding model. The high-frequency Hall constant in this system is potentially interesting, since it is pointed out to increase linearly with temperature without saturation for T>Tdegeneracy.