Superconductivity in Na$_{x}$CoO$_{2}\cdot y$H$_{2}$O driven by the kinetic energy

Bin Liu; Ying Liang; Shiping Feng

doi:10.1142/s0217979205027962

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Superconductivity in Na$_{x}$CoO$_{2}\cdot y$H$_{2}$O driven by the kinetic energy

Bin Liu·Ying Liang·Shiping Feng

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Abstract

Within the charge-spin separation fermion-spin theory, the mechanism of superconductivity in Na$_{x}$CoO$_{2}\cdot y$H$_{2}$O is studied. It is shown that dressed fermions interact occurring directly through the kinetic energy by exchanging magnetic excitations. This interaction leads to a net attractive force between dressed fermions(then the electron Cooper pairs), and their condensation reveals the superconducting ground state. The optimal superconducting transition temperature occurs in the electron doping concentration $δ\approx 0.29$, and then decreases for both underdoped and overdoped regimes, in qualitative agreement with the experimental results.

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Bin Liu, Ying Liang, Shiping Feng. 2005-05-10. Superconductivity in Na$_{x}$CoO$_{2}\cdot y$H$_{2}$O driven by the kinetic energy. https://doi.org/10.1142/s0217979205027962

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