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The Role of Thermal Phase Fluctuations in Underdoped YBCO Films

Yuri Zuev·John A. Skinta·Mun-Seog Kim·Thomas R. Lemberger·E. Wertz·K. Wu·Q. Li
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Abstract

The effect of thermal phase fluctuations (TPF's) on the ab-plane penetration depth, lambda(T), of thin YBa2Cu3O(7-delta) (YBCO) films is found to be much smaller than expected from the paradigm of cuprates as weakly-coupled 2D superconducting layers. A 2D vortex-pair-unbinding transition is observed, but the effective thickness for fluctuations is the film thickness, not a CuO bilayer thickness. In a strongly underdoped YBCO film, Tc= 34 K, TPF's suppress Tc by only about 3 K. They cannot be a significant factor in the suppression of Tc and emergence of the pseudogap with underdoping.

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Yuri Zuev, John A. Skinta, Mun-Seog Kim, Thomas R. Lemberger, E. Wertz, K. Wu, Q. Li. 2004-07-06. The Role of Thermal Phase Fluctuations in Underdoped YBCO Films. https://arxiv.org/abs/cond-mat/0407113

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