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arXiv · 1706.07618

The effects of oxygen in spinel oxide Li1+xTi2-xO4-delta thin films

Yanli Jia·Ge He·Wei Hu·Hua Yang·Zhenzhong Yang·Heshan Yu·Qinghua Zhang·Jinan Shi·Zefeng Lin·Jie Yuan·Beiyi Zhu·Lin Gu·Hong Li·Kui Jin
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Abstract

The evolution from superconducting LiTi2O4-delta to insulating Li4Ti5O12 thin films has been studied by precisely adjusting the oxygen pressure during the sample fabrication process. In the superconducting LiTi2O4-delta films, with the increase of oxygen pressure, the oxygen vacancies are filled, and the c-axis lattice constant decreases gradually. With the increase of the oxygen pressure to a certain critical value, the c-axis lattice constant becomes stable, which implies that the Li4Ti5O12 phase comes into being. The process of oxygen filling is manifested by the angular bright-field images of the scanning transmission electron microscopy techniques. The temperature of magnetoresistance changed from positive and negative shows a non-monotonous behavior with the increase of oxygen pressure. The theoretical explanation of the oxygen effects on the structure and superconductivity of LiTi2O4-delta has also been discussed in this work.

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Yanli Jia, Ge He, Wei Hu, Hua Yang, Zhenzhong Yang, Heshan Yu, Qinghua Zhang, Jinan Shi, Zefeng Lin, Jie Yuan, Beiyi Zhu, Lin Gu, Hong Li, Kui Jin. 2017-06-23. The effects of oxygen in spinel oxide Li1+xTi2-xO4-delta thin films. https://arxiv.org/abs/1706.07618

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