Precursor Pairing Correlations and Pseudogaps

Mohit Randeria

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arXiv · cond-mat/9710223

Precursor Pairing Correlations and Pseudogaps

Mohit Randeria

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Abstract

I begin by briefly reviewing various experimental results on the pseudogap phenomena in underdoped cuprates. I argue that, taken together, all of these lead to a picture of singlet pairing above $T_c$. I then explore the idea that the pseudogap is a normal state precursor of the superconducting gap due to local, dynamic pairing correlations in a state without long range phase coherence. Early work on simple model systems which exhibit pseudogap anomalies in the normal state of 2D superconductors in a low density, small pair size regime is reviewed and critically re-examined in view of more recent developments. I also describe recent studies of how the underlying d-wave superconducting ground state affects the anisotropy of the pseudogap and the destruction of the Fermi surface.

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Mohit Randeria. 1997-10-21. Precursor Pairing Correlations and Pseudogaps. https://arxiv.org/abs/cond-mat/9710223

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