Anomalous transport and structural properties of Sr1−xCuO2−δ thin films

doi:10.1016/0921-4534(93)90804-Y

Physica C: Superconductivity

Volume 217, Issues 1–2, 10 November 1993, Pages 146-150

https://doi.org/10.1016/0921-4534(93)90804-Y Get rights and content

Abstract

Transport and structural properties of Sr_1−xCuO_2−δ thin films grown by pulsed laser deposition support the contention that the tetragonal phase is capable of accommodating a significant density of alkaline-earth deficiencies up to x≤0.3. Resistivity measurements indicate a significant change in the carrier density of the CuO₂ planes as Sr vacancies are introduced. In addition, an enigmatic anomaly in the resistivity at 185 K is observed for Sr_0.85CuO_2−δ thin films. Magnetic measurements on these samples indicate that, although a significant drop in resistivity at 185 K is observed, it is not due to a superconducting transition. Hall measurements, as well as changes in the resistivity with film growth conditions, suggest that the majority carriers in these Sr_1−xCuO_2−δ thin films are electrons even with the Sr-vacancies present.

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