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arXiv · 0911.4102

Scaling of the superfluid density in severely underdoped YBa2Cu3O6+y

C. C. Homes
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Abstract

Recent measurements on extremely-underdoped YBa2Cu3O6+y [Phys. Rev. Lett. 99, 237003 (2007)] have allowed the critical temperature (T_c), superfluid density [rho_0 (T << T_c)] and dc conductivity [sigma_dc (T ~ T_c)] to be determined for a series of electronic dopings for T_c ~ 3 - 17 K. The general scaling relation rho_0/8 ~ 4.4 sigma_dc T_c is observed, extending the validity of both the ab-plane and c-axis scaling an order of magnitude and creating a region of overlap. This suggests that severely underdoped materials may constitute a Josephson phase; as the electronic doping is increased a more uniform superconducting state emerges.

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C. C. Homes. 2009-11-20. Scaling of the superfluid density in severely underdoped YBa2Cu3O6+y. https://doi.org/10.1103/physrevb.80.180509

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