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arXiv · 0711.1192

Superfluid Density in High-$T_c$ Superconductors: Enabled by Holes or Suppressed by Electrons?

Wei-Cheng Lee·Jairo Sinova·A. A. Burkov·Yogesh Joglekar·A. H. MacDonald
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Abstract

The critical temperature of an underdoped cuprate superconductor is limited by its phase stiffness $ρ$. In this Letter we argue that the dependence of $ρ$ on doping $x$ should be understood as a consequence of deleterious competition with antiferromagnetism at large electron densities, rather than as evidence for pairing of holes in the $x =0$ Mott insulator state. Our proposal is based on the observation that the correlation energy of a d-wave superconductor increases in magnitude at finite pairing wavevector when antiferromagnetic fluctuations are strong.

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Wei-Cheng Lee, Jairo Sinova, A. A. Burkov, Yogesh Joglekar, A. H. MacDonald. 2008-05-30. Superfluid Density in High-$T_c$ Superconductors: Enabled by Holes or Suppressed by Electrons?. https://doi.org/10.1103/physrevb.77.214518

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