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arXiv · 0803.3052

Evidence for pairing above Tc from the dispersion in the pseudogap phase of cuprates

A. Kanigel·U. Chatterjee·M. Randeria·M. R. Norman·G. Koren·K. Kadowaki·J. C. Campuzano
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Abstract

In the underdoped high temperature superconductors, instead of a complete Fermi surface above Tc, only disconnected Fermi arcs appear, separated by regions that still exhibit an energy gap. We show that in this pseudogap phase, the energy-momentum relation of electronic excitations near E_F behaves like the dispersion of a normal metal on the Fermi arcs, but like that of a superconductor in the gapped regions. We argue that this dichotomy in the dispersion is hard to reconcile with a competing order parameter, but is consistent with pairing without condensation.

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A. Kanigel, U. Chatterjee, M. Randeria, M. R. Norman, G. Koren, K. Kadowaki, J. C. Campuzano. 2008-03-20. Evidence for pairing above Tc from the dispersion in the pseudogap phase of cuprates. https://doi.org/10.1103/physrevlett.101.137002

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