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arXiv · 1309.1295

Persistent photoconductivity in oxygen deficient YBCO/LCMO superlattices grown by PLD

K. Kawashima·S. Soltan·G. Logvenov·H. -U. Habermeier
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Abstract

We report a large persistent photoconductivity (PPC) in oxygen reduced PLD grown YBa2Cu3O7-δ/La2/3Ca1/3MnO3-y (YBCO/LCMO) superlattices scaling with the oxygen deficiency and being similar to that observed in single layer YBa2Cu3O7-δ films. These results contradict previous observations where in sputtered bilayer samples only a transient photoconductivity (TPC) was found. We argue that the PPC effect in superlattices is caused by the PPC effect due to the YBa2Cu3O7-x layers with limited charge transfer to La2/3Ca1/3MnO3-y. The discrepancy arises from the different permeability of charges across the interface and shed light on the sensitivity of oxide interface properties on details of their preparation.

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K. Kawashima, S. Soltan, G. Logvenov, H. -U. Habermeier. 2013-09-05. Persistent photoconductivity in oxygen deficient YBCO/LCMO superlattices grown by PLD. https://arxiv.org/abs/1309.1295

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