Superconductivity above 100 K in single-layer FeSe films on doped SrTiO3
Superconductivity above 100 K in single-layer FeSe films on doped SrTiO3
复制标题
掺杂 SrTiO3 上的单层 FeSe 薄膜具有 100 K 以上的超导性
DOI：
10.1038/nmat4153
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发表时间：
2015-03-01
期刊：
影响因子：
41.2
通讯作者：
Jia, Jin-Feng
中科院分区：
文献类型：
--
作者：
Ge, Jian-Feng;Liu, Zhi-Long;Jia, Jin-Feng
最近在SrTiO 3（STO）上生长的FeSe薄膜的实验表明，界面效应可以用作达到高达80 K的超导临界温度（Tc）的一种手段（参考文献1）。这几乎是块状FeSe的T-c的十倍，并且高于已知块状Fe基超导体的56 K的记录值（2）。再加上最近对氧化物异质结构界面处超导性的研究（3-6），这些结果重新点燃了长期存在的想法，即两种不同材料之间界面处的电子配对可以定制以实现高温超导性（7-12）。随后对FeSe = STO系统的角度分辨光电子能谱测量揭示了与体FeSe不同的电子结构（参考文献13，14），在65 K附近能隙消失。然而，非原位电输运测量（1，15）迄今为止只在30 K以下检测到零电阻-超导性的关键实验特征。在这里，我们报告的观察超导体的Tc高于100 K的FeSe = STO系统通过原位四点探针电输运测量。这一发现证实了FeSe/STO是研究高温超导性的理想材料。
Recent experiments on FeSe films grown on SrTiO3 (STO) suggest that interface effects can be used as a means to reach superconducting critical temperatures (T-c) of up to 80 K (ref. 1). This is nearly ten times the T-c of bulk FeSe and higher than the record value of 56 K for known bulk Fe-based superconductors(2). Together with recent studies of superconductivity at oxide heterostructure interfaces(3-6), these results rekindle the long-standing idea that electron pairing at interfaces between two different materials can be tailored to achieve high-temperature superconductivity(7-12). 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 measurements(1,15) have so far detected zero resistance-the key experimental signature of superconductivity-only below 30 K. Here, we report the observation of superconductivity with T-c 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-T-c superconductivity.