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Superconductivity above 100 K in single-layer FeSe films on doped SrTiO3

Nature Materials volume 14, pages 285289 (2015) | Download Citation

Abstract

Recent experiments on FeSe films grown on SrTiO3 (STO) suggest that interface effects can be used as a means to reach superconducting critical temperatures (Tc) of up to 80 K (ref. 1). This is nearly ten times the Tc of bulk FeSe and higher than the record value of 56 K for known bulk Fe-based superconductors2. Together with recent studies of superconductivity at oxide heterostructure interfaces3,4,5,6, these results rekindle the long-standing idea that electron pairing at interfaces between two different materials can be tailored to achieve high-temperature superconductivity7,8,9,10,11,12. Subsequent angle-resolved photoemission spectroscopy measurements of the FeSe/STO system revealed an electronic structure distinct from bulk FeSe (refs 13, 14), with an energy gap vanishing at around 65 K. However, ex situ electrical transport measurements1,15 have so far detected zero resistance—the key experimental signature of superconductivity—only below 30 K. Here, we report the observation of superconductivity with Tc above 100 K in the FeSe/STO system by means of in situ four-point probe electrical transport measurements. This finding confirms FeSe/STO as an ideal material for studying high-Tc superconductivity.

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Acknowledgements

We acknowledge helpful discussions with X. Ma, L. Wang, W. Zhang, D. Feng, F. Zhang, N. Samarth and T. Leggett. Financial support from the National Basic Research Program of China (Grant Nos 2012CB927400, 2011CB921902, 2013CB921902 and 2011CB922200), NSFC (Grant Nos 11227404, 11374206, 91021002, 11274228, 10904090, 11174199, 11134008, 11274229 and 1147198) and the Shanghai Committee of Science and Technology, China (Grant Nos 12JC1405300, 13QH1401500 and 10JC1407100) is gratefully acknowledged.

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Affiliations

  1. Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), Department of Physics and Astronomy, Shanghai Jiao Tong University, 800 Dongchuan Road Shanghai 200240, China

    • Jian-Feng Ge
    • , Zhi-Long Liu
    • , Canhua Liu
    • , Chun-Lei Gao
    • , Dong Qian
    • , Ying Liu
    •  & Jin-Feng Jia
  2. Collaborative Innovation Center of Advanced Microstructures, Nanjing 210093, China

    • Canhua Liu
    • , Chun-Lei Gao
    • , Dong Qian
    • , Ying Liu
    •  & Jin-Feng Jia
  3. Department of Physics, Tsinghua University, Beijing 100084, China

    • Qi-Kun Xue
  4. Department of Physics and Materials Research Institute, Pennsylvania State University, University Park, Pennsylvania 16802, USA

    • Ying Liu

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Contributions

J-F.G. and Z-L.L. conducted the experiments. C.L., Q-K.X. and J-F.J. designed the experiments and provided financial and other supports for the experiments. C.L, Y.L., Q-K.X., J-F.G., C-L.G., D.Q. and J-F.J. analysed the data. C.L, Y.L., Q-K.X., and J-F.J. wrote the paper.

Competing interests

The authors declare no competing financial interests.

Corresponding authors

Correspondence to Canhua Liu or Qi-Kun Xue or Jin-Feng Jia.

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DOI

https://doi.org/10.1038/nmat4153

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