The enigma of the pseudogap phase of the cuprate superconductors

Debanjan Chowdhury; Subir Sachdev

doi:10.1142/9789814704090_0001

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arXiv · 1501.00002

The enigma of the pseudogap phase of the cuprate superconductors

Debanjan Chowdhury·Subir Sachdev

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Abstract

The last few years have seen significant experimental progress in characterizing the copper-based hole-doped high temperature superconductors in the regime of low hole density, p. Quantum oscillations, NMR, X-ray, and STM experiments have shed much light on the nature of the ordering at low temperatures. We review evidence that the order parameter in the non-Lanthanum-based cuprates is a d-form factor density-wave. This novel order acts as an unexpected window into the electronic structure of the pseudogap phase at higher temperatures in zero field: we argue in favor of a `fractionalized Fermi liquid' (FL*) with 4 pockets of spin S=1/2, charge +e fermions enclosing an area specified by p.

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Debanjan Chowdhury, Subir Sachdev. 2014-12-30. The enigma of the pseudogap phase of the cuprate superconductors. https://doi.org/10.1142/9789814704090_0001

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