Emergence of superconducting dome in insulating ZrNx films via nitrogen manipulation

Fucong Chen; Xinbo Bai; Yuxin Wang; Tao Dong; Jinan Shi; Yanmin Zhang; Xiaomin Sun; Zhongxu Wei; Mingyang Qin; Jie Yuan; Qihong Chen; Xinbo Wang; Xu Wang; Beiyi Zhu; Rongjin Huang; Kun Jiang; Wu Zhou; Nanlin Wang; Jiangping Hu; Yangmu Li; Kui Jin; Zhongxian Zhao

arXiv · 2201.04340

Emergence of superconducting dome in insulating ZrNx films via nitrogen manipulation

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Abstract

Reproducing the electronic phase diagram of strongly correlated high-transition-temperature (high-Tc) superconductors in materials other than Cu-, Fe-, and Ni-based compounds has been a challenging task. Only very recently, a few material systems have partially achieved this goal by band engineering. In this work, we combine film growth, charge transport, magnetometry, Terahertz Spectroscopy, Raman scattering, and Scanning Transmission Electron Microscopy to investigate superconductivity and the normal state of ZrNx, which reveals a phase diagram that bears extraordinary similarities to those of high-Tc superconductors. Remarkably, even though superconductivity of ZrNx can be characterized within the Bardeen-Cooper-Schrieffer paradigm and its normal state can be understood within the Fermi liquid framework, by tunning the N chemical concentration, we observe the evolution of a superconducting dome in the close vicinity of a strongly insulating state and a normal state resistivity mimics its counterpart of the high-Tc superconductors.

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Fucong Chen, Xinbo Bai, Yuxin Wang, Tao Dong, Jinan Shi, Yanmin Zhang, Xiaomin Sun, Zhongxu Wei, Mingyang Qin, Jie Yuan, Qihong Chen, Xinbo Wang, Xu Wang, Beiyi Zhu, Rongjin Huang, Kun Jiang, Wu Zhou, Nanlin Wang, Jiangping Hu, Yangmu Li, Kui Jin, Zhongxian Zhao. 2022-01-12. Emergence of superconducting dome in insulating ZrNx films via nitrogen manipulation. https://arxiv.org/abs/2201.04340

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