ANOMALOUS SPIN DENSITY WAVE SUPERCONDUCTIVITY IN CUPRATE HIGH-Tc SUPERCONDUCTORS

摘要

Spin density waves (SDWs) may be thought of as comprising charge density waves (CDWs) in pairs, with one CDW composed of up-spin electrons and the other composed of down-spin electrons. The superconductivity in cuprates may then be said to be caused by the BCS-type pairing of these SDWs. This is no longer a simple Cooper pairing of singlet electrons but one that involves a collection of Cooper pairs. Transport in normal metallic states is then governed by CDW pinning, as in a quantum well that is characterized by linear temperature dependence. The pseudo-gap may be understood as originating from this BCS-type gap with SDW, where the parameters used are from those of the original BCS scheme except that the electron{electron interaction is multiplied by NCDW, which is the number of electrons that have the same spin direction belonging to one CDW branch of the pair that comprises the SDW.