Superconductivity above 28 K in single unit cell FeSe films interfaced with GaO$_{2-\delta}$ layer on NdGaO$_{3}$(110)

Haohao Yang; Guanyu Zhou; Yuying Zhu; Guan-Ming Gong; Qinghua Zhang; Menghan Liao; Zheng Li; Cui Ding; Fanqi Meng; Mohsin Rafique; Heng Wang; Lin Gu; Ding Zhang; Lili Wang; Qi-Kun Xue

arXiv · 1901.06104

Superconductivity above 28 K in single unit cell FeSe films interfaced with GaO$_{2-\delta}$ layer on NdGaO$_{3}$(110)

Haohao Yang·Guanyu Zhou·Yuying Zhu·Guan-Ming Gong·Qinghua Zhang·Menghan Liao·Zheng Li·Cui Ding·Fanqi Meng·Mohsin Rafique·Heng Wang·Lin Gu·Ding Zhang·Lili Wang·Qi-Kun Xue

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Abstract

We prepared single unit cell FeSe films on GaO$_{2-\delta}$ terminated perovskite NdGaO$_{3}$(110) substrates and performed ex situ transport and scanning transmission electron microscopy measurements on the FeTe protected films. Our experimental measurements showed that the single unit cell FeSe films interfaced with GaO$_{2-{\delta}}$ layer are electron doped via interface charge transfer. Most importantly, this type of heterostructure can host interface enhanced superconductivity with an onset temperature of about 28 K, which is much higher than the value of 8 K in bulk FeSe. Our work indicates that FeSe/GaO$_{2-{\delta}}$can be a comparative platform with the FeSe/TiO$_{2-{\delta}}$ family for understanding the mechanism of interface enhanced high temperature superconductivity.

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Haohao Yang, Guanyu Zhou, Yuying Zhu, Guan-Ming Gong, Qinghua Zhang, Menghan Liao, Zheng Li, Cui Ding, Fanqi Meng, Mohsin Rafique, Heng Wang, Lin Gu, Ding Zhang, Lili Wang, Qi-Kun Xue. 2019-01-18. Superconductivity above 28 K in single unit cell FeSe films interfaced with GaO$_{2-\delta}$ layer on NdGaO$_{3}$(110). https://arxiv.org/abs/1901.06104

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