Interfacial superconductivity in a bi-collinear antiferromagnetically ordered FeTe monolayer on a topological insulator.
Interfacial superconductivity in a bi-collinear antiferromagnetically ordered FeTe monolayer on a topological insulator.
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拓扑绝缘子上双线性抗磁性降解单层的界面超导性。
DOI：
10.1038/ncomms14074
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发表时间：
2017-01-17
影响因子：
16.6
通讯作者：
Wiesendanger R
中科院分区：
文献类型：
--
作者：
Manna S;Kamlapure A;Cornils L;Hänke T;Hedegaard EM;Bremholm M;Iversen BB;Hofmann P;Wiebe J;Wiesendanger R
铁基化合物高温超导性的发现引发了对超导性和磁性之间相互作用的大量研究，以及通过界面效应提高转变温度。人们普遍认为，最佳超导性的出现与长程反铁磁（AFM）有序的抑制密切相关，尽管由于缺乏原子分辨数据，精确的微观图像仍然难以捉摸。在这里，我们提出了自旋极化扫描隧道光谱的块状拓扑绝缘体上的FeTe 1 −xSex（x=0，0.5）薄膜。令人惊讶的是，我们发现一个能隙在费米能级，表明超导相关性高达Tc <$6 K的一个单元电池上生长的Bi 2 Te 3，在非超导体FeTe。差距与双共线原子力显微镜有序度在空间上共存。这一发现为铁基超导体中竞争有序的理论研究和拓扑绝缘体上超导层中奇异相的实验研究开辟了前景。在铁基化合物中，超导性如何与反铁磁有序相联系的微观图景仍然难以捉摸。在这里，Manna等人报道了在Bi 2 Te 3上生长的FeTe的一个晶胞薄层中与双共线反铁磁序空间共存的超导相关性。
The discovery of high-temperature superconductivity in Fe-based compounds triggered numerous investigations on the interplay between superconductivity and magnetism, and on the enhancement of transition temperatures through interface effects. It is widely believed that the emergence of optimal superconductivity is intimately linked to the suppression of long-range antiferromagnetic (AFM) order, although the exact microscopic picture remains elusive because of the lack of atomically resolved data. Here we present spin-polarized scanning tunnelling spectroscopy of ultrathin FeTe1−xSex (x=0, 0.5) films on bulk topological insulators. Surprisingly, we find an energy gap at the Fermi level, indicating superconducting correlations up to Tc∼6 K for one unit cell FeTe grown on Bi2Te3, in contrast to the non-superconducting bulk FeTe. The gap spatially coexists with bi-collinear AFM order. This finding opens perspectives for theoretical studies of competing orders in Fe-based superconductors and for experimental investigations of exotic phases in superconducting layers on topological insulators. The microscopic picture of how superconductivity is linked to antiferromagnetic order in Fe-based compounds remains elusive. Here, Manna et al. report superconducting correlations which spatially coexist with bi-collinear antiferromagnetic order in a one unit cell thin layer of FeTe grown on Bi2Te3.