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arXiv · 2501.16278

Electric transport as a probe to unveil microscopic aspects of oxygen-depleted YBCO

C. Acha·A. Camjayi·T. Vaimala·H. Huhtinen·P. Paturi
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Abstract

We report on the characterization of Pt-YBa$_2$Cu$_3$O$_{7-\delta}$ interfaces, focusing on how oxygen vacancies content ($\delta$) affects electrical transport mechanisms. Our study examines four Pt-YBa$_2$Cu$_3$O$_{7-\delta}$ samples with varying $\delta$ (0.12 $\leq \delta \leq$ 0.56) using voltage-current measurements across a temperature range. We successfully model the electrical behavior using a Poole-Frenkel conduction framework, revealing that oxygen vacancies create potential wells that trap carriers, directly influencing conduction. We observe that the energy of these traps increases as $\delta$ rises, in agreement with a peak previously detected in optical conductivity measurements. This result supports earlier interpretations, strengthening the proposed connection between oxygen vacancies and the ionization energy associated with impurity bands in YBa$_2$Cu$_3$O$_{7-\delta}$.

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C. Acha, A. Camjayi, T. Vaimala, H. Huhtinen, P. Paturi. 2025-01-27. Electric transport as a probe to unveil microscopic aspects of oxygen-depleted YBCO. https://doi.org/10.1016/j.jallcom.2025.178760

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