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Phenomenological model of protected behavior in the cuprate superconductors

Victor Barzykin·David Pines
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Abstract

By extending previous work on the scaling of low frequency magnetic properties of the 2-1-4 cuprates to the 1-2-3 materials, we arrive at a consistent phenomenological description of protected behavior in the pseudogap state of the magnetically underdoped cuprates. Between zero hole doping and a doping level of $\sim 0.22$ it reflects the presence of a mixture of an insulating spin liquid that produces the measured magnetic scaling behavior and a Fermi liquid that becomes superconducting for doping levels $x>0.06$. Our analysis suggests the existence of two quantum critical points, at doping levels, $x \sim 0.05$ and $x \sim 0.22$, and that d-wave superconductivity in the pseudogap region arises from quasiparticle-spin liquid interaction, i.e. magnetic interactions between quasiparticles in the Fermi liquid induced by their coupling to the spin liquid excitations.

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Victor Barzykin, David Pines. 2006-03-29. Phenomenological model of protected behavior in the cuprate superconductors. https://doi.org/10.1103/physrevlett.96.247002

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