Letter | Published:

Liquid-gated interface superconductivity on an atomically flat film

Nature Materials volume 9, pages 125128 (2010) | Download Citation

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Abstract

Liquid/solid interfaces are attracting growing interest not only for applications in catalytic activities and energy storage1,2, but also for their new electronic functions in electric double-layer transistors (EDLTs) exemplified by high-performance organic electronics3,4,5,6,7, field-induced electronic phase transitions8,9,10,11, as well as superconductivity in SrTiO3 (ref. 12). Broadening EDLTs to induce superconductivity within other materials is highly demanded for enriching the materials science of superconductors. However, it is severely hampered by inadequate choice of materials and processing techniques13. Here we introduce an easy method using ionic liquids as gate dielectrics, mechanical micro-cleavage techniques for surface preparation, and report the observation of field-induced superconductivity showing a transition temperature Tc=15.2 K on an atomically flat film of layered nitride compound, ZrNCl. The present result reveals that the EDLT is an extremely versatile tool to induce electronic phase transitions by electrostatic charge accumulation and provides new routes in the search for superconductors beyond those synthesized by traditional chemical methods.

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Acknowledgements

We thank D. Chiba, Y. Ohno, F. Matsukura and H. Ohno for providing the electron beam lithography facility at the Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University. We also thank T. Takano, Y. Taguchi, K. Ueno, A. Tsukazaki, A. Ohtomo and M. Kawasaki for stimulating discussions. This research is financially supported by MEXT and JST.

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Affiliations

  1. Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan

    • J. T. Ye
    • , S. Inoue
    • , K. Kobayashi
    • , Y. Kasahara
    • , H. T. Yuan
    • , H. Shimotani
    •  & Y. Iwasa
  2. Institute for International Advanced Interdisciplinary Research, Tohoku University, Sendai 980-8578, Japan

    • J. T. Ye
  3. Japan Science and Technology Agency (CREST), Saitama 332-0012, Japan

    • H. T. Yuan
    • , H. Shimotani
    •  & Y. Iwasa

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Contributions

K.K. and Y.K. fabricated the pristine ZrNCl single crystals. H.T.Y. and H.S. tested the performance of ionic liquids. J.T.Y. and S.I. fabricated the EDLT devices. J.T.Y. carried out all of the measurements and analysed the data. J.T.Y. and Y.I. wrote the paper.

Corresponding authors

Correspondence to J. T. Ye or Y. Iwasa.

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https://doi.org/10.1038/nmat2587

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