Observation of the gap distribution on multi-layered cuprate superconductor Ba2Ca4Cu5O10(O1-xFx)2 by STM/STS
Observation of the gap distribution on multi-layered cuprate superconductor Ba2Ca4Cu5O10(O1-xFx)2 by STM/STS
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STM/STS观察多层铜酸盐超导体Ba2Ca4Cu5O10(O1-xFx)2的能隙分布
DOI：
10.1016/j.phpro.2014.09.023
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发表时间：
2014
期刊：
影响因子：
--
通讯作者：
K. Tokiwa
中科院分区：
文献类型：
--
作者：
A. Sugimoto;T. Ekino;K. Tanaka;K. Mineta;K. Tanabe;K. Tokiwa
用扫描隧道显微镜/光谱（STM/STS）研究了顶部含氟多层铜酸盐超导体Ba 2Ca 4Cu 5 O 10（O 1-x，Fx）（F0245，Tc= 70 K）的纳米尺度空间带隙分布. STM图像显示随机分布的亮点结构，其被分配给未被取代的顶端氧。dI/dV隧道谱表明两种差距结构共存。在4.9 K时，这些能隙的大小分别约为ΔS <$25 meV和ΔL <$78 meV。ΔLmap显示了特征长度为0.1nm的不均匀分布。较小的ΔLgap区域倾向于位于亮点位置，表明顶端氧导致ΔL减小。这些结果是一致的载流子掺杂水平和宏观观察到的间隙大小之间的公知的关系。
The nano-scale spatial gap distributions on apical-fluorine multi-layered cuprate superconductors Ba2Ca4Cu5O10(O1-x, Fx) (F0245,Tc= 70 K) are investigated by scanning tunneling microscopy/spectroscopy (STM/STS). The STM image shows randomly-distributed bright spot structures, which are assigned to the non-replaced apical oxygen. The dI/dVtunnel spectra show the coexistence of two kinds of the gap structures. The magnitudes of these gaps at 4.9 K are about ΔS∼25 meV and ΔL∼78 meV, respectively. The ΔLmap shows the inhomogeneous distribution with the characteristic length of ∼1 nm. The smaller ΔLgap regions tend to locate at the bright-spot positions, indicating that the apical oxygen causes reduction of ΔL. These results are consistent with the well known relation between the carrier doping level and macroscopically observed gap size.