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Title: Enhancing superconductivity in SrTiO 3 films with strain
The nature of superconductivity in SrTiO 3 , the first oxide superconductor to be discovered, remains a subject of intense debate several decades after its discovery. SrTiO 3 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 SrTiO 3 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.  more » « less
Award ID(s):
1740213 1729489
Author(s) / Creator(s):
; ; ; ; ;
Date Published:
Journal Name:
Science Advances
Page Range / eLocation ID:
Medium: X
Sponsoring Org:
National Science Foundation
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