Topological states in engineered atomic lattices
Topological states in engineered atomic lattices
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DOI：
10.1038/nphys4080
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发表时间：
2017-07-01
期刊：
影响因子：
19.6
通讯作者：
Liljeroth, Peter
中科院分区：
文献类型：
--
作者：
Drost, Robert;Ojanen, Teemu;Liljeroth, Peter
拓扑材料表现出已被提出用于例如自旋电子学和量子计算中的应用的受保护的边缘模式。尽管存在许多这样的系统（1-6），但希望能够在允许精确控制模型的关键参数的人工系统中测试理论建议（7）。几个拓扑系统的基本物理可以通过紧束缚模型来捕获，这些模型也可以在人工晶格中实现（6，7）。在这里，我们表明，这种方法可以实现在Cu（100）表面上的氯单分子层的空位晶格。我们使用低温扫描隧道显微镜（STM）制造这样的晶格与原子精度和探测所得的局域态密度（LDOS）与扫描隧道光谱（STS）。我们创建的两个紧密结合的模型的基本重要性的类似物：聚乙炔（二聚体）链与拓扑结构域壁状态，和Lieb晶格与平坦的电子带。这些结果为实现具有定制特性的设计师量子材料的持续努力迈出了重要的一步。
Topological materials exhibit protected edge modes that have been proposed for applications in, for example, spintronics and quantum computation. Although a number of such systems exist(1-6), it would be desirable to be able to test theoretical proposals in an artificial system that allows precise control over the key parameters of the model(7). The essential physics of several topological systems can be captured by tight-binding models, which can also be implemented in artificial lattices(6,7). Here, we show that this method can be realized in a vacancy lattice in a chlorine monolayer on a Cu(100) surface. We use low-temperature scanning tunnelling microscopy (STM) to fabricate such lattices with atomic precision and probe the resulting local density of states (LDOS) with scanning tunnelling spectroscopy (STS). We create analogues of two tight-binding models of fundamental importance: the polyacetylene (dimer) chain with topological domain-wall states, and the Lieb lattice with a flat electron band. These results provide an important step forward in the ongoing effort to realize designer quantum materials with tailored properties.