论文标题
通过扫描隧道光谱观察薄PB膜中位错环的隐藏部分
Observation of hidden parts of dislocation loops in thin Pb films by means of scanning tunneling spectroscopy
论文作者
论文摘要
在恒定电流的恒定电流状态下，通过低温扫描隧道显微镜和光谱法对表面上不同类型的表面上不同类型的螺钉脱位的局部电子性质（111）岛进行了实验研究。比较地形图，隧穿电流变化的图和差分隧穿电导，同时获得了一个人，使一个人可以看到样品表面下位错环的隐藏部分。我们证明，两个与相反汉堡向量的紧密位置的螺钉位错可以（i）通过地下脱位环相互连接，或者（ii）生成朝向PB岛周围的独立隐藏边缘位错线。此外，我们发现了一个螺钉脱位，该螺钉位错不会产生次要的地下脱位环。螺钉位错和隐藏位错线是PB梯田局部厚度的非定量变化的来源，影响了局部电子特性。
Local electronic properties of quasi-two-dimensional Pb(111) islands with screw dislocations of different types on their surfaces were experimentally studied by means of low-temperature scanning tunneling microscopy and spectroscopy in the regime of constant current. A comparison of the topography map, the maps of tunneling current variation and the differential tunneling conductance acquired simultaneously allows one to visualize the hidden parts of the dislocation loops under the sample surface. We demonstrate that two closely-positioned screw dislocations with the opposite Burgers vectors can either (i) connect to each other by the sub-surface dislocation loop or (ii) generate independent hidden edge dislocation lines which run towards the perimeter of the Pb island. In addition, we found a screw dislocation, which does not produce outcoming sub-surface dislocation loops. Screw dislocations and the hidden dislocations lines are the source of the non-quantized variation of the local thickness of the Pb terraces, affecting the local electronic properties.
