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arXiv · 0712.0936

Doping dependence of the vortex-core energy in bilayer films of cuprates

L. Benfatto·C. Castellani·T. Giamarchi
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Abstract

The energy needed to create a vortex core is the basic ingredient to address the physics of thermal vortex fluctuations in underdoped cuprates. Here we theoretically investigate its role on the occurrence of the Beresinskii-Kosterlitz-Thouless transition in a bilayer film with inhomogeneity. From the comparison with recent measurements of the penetration depth in two-unit cell thin films of Y$_{1-x}$Ca$_{x}$Ba$_{2}$Cu$_{3}$O$_{7-\d}$ (YBCO) by Hetel et al. [Nat. Phys. 3, 700 (2007)] we can extract the value of the vortex-core energy $μ$, and show that $μ$ scales linearly with $T_c$ at low doping.

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L. Benfatto, C. Castellani, T. Giamarchi. 2008-04-08. Doping dependence of the vortex-core energy in bilayer films of cuprates. https://doi.org/10.1103/physrevb.77.100506

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