Enhancing superconductivity in SrTiO3 films with strain

The nature of superconductivity in SrTiO3, the first oxide superconductor to be discovered, remains a subject of intense debate several decades after its discovery. SrTiO3 is also an incipient ferroelectric, and several recent theoretical studies have suggested that the two properties may be linked. To investigate whether such a connection exists, we grew strained, epitaxial SrTiO3 films, which are known to undergo a ferroelectric transition. We show that, for a range of carrier densities, the superconducting transition temperature is enhanced by up to a factor of two compared to unstrained films grown under the same conditions. Moreover, for these films, superconductivity emerges from a resistive state. We discuss the localization behavior in the context of proximity to ferroelectricity. The results point to new opportunities to enhance superconducting transition temperatures in oxide materials.

Progress in the research of copper-oxide superconductors

Since H·Carvalin·Onnesse discovered the superconductivity of mercury in 1911, we have made progress in the research of the superconductor and the superconductor have evolved from single element, alloy to complex compounds with multiple elements.With the development of the research about new superconducting materials, the research of iron based superconductors, copper-oxide superconductor and magnesium boride superconductor is the latest research trend. So far the proved highest superconducting transition temperature of copper-oxide superconductor is 130 K under normal pressure and could reach more than 160 K under high pressure. Based on the experience accumulated in past decades, we propose some general introduction about the main structure type, the superconducting principle and the application of copper-oxide superconductor.It is expected that a positive effect would be made in the research of copper-oxide superconductor. Background: Since H·Carvalin·Onnesse discovered the superconductivity of mercury in 1911, we have made progress in the research of the superconductor and the superconductor have evolved from single element, alloy to complex compounds with multiple elements. Aim: The purpose of this paper is to explain the differences between copper oxide superconductors and conventional superconductors and their superconducting mechanism. Methods: The superconducting mechanism and structure of copper oxide superconductors were analyzed by means of literature investigation, conceptual analysis and comparative study. Results: In this paper, the different structure forms of copper oxide are analyzed, and its superconducting mechanism is described in detail. The applications of several main copper oxide superconductors are introduced. Conclusion: Based on the experience accumulated in past decades, we propose some general introduction about the main structure type, the superconducting principle and the application of copper-oxide superconductor.It is expected that a positive effect would be made in the research of copper-oxide superconductor.