标题： 硅纳米带上的单维钾链 显示英文标题

标题： One-Dimensional Potassium Chains on Silicon Nanoribbons

摘要： 硅纳米带（SiNRs），由五边形结构的硅原子组成，具有一维（1D）狄拉克费米子，并且作为吸附各种异原子的最简原子模板。碱金属（AM）原子，如钠（Na）和钾（K），其电子结构与氢类似，对此类吸附研究特别感兴趣。然而，AM原子在SiNRs上的吸附及其对SiNRs性质的调节尚未得到充分探索。在这项研究中，我们使用扫描隧道显微镜（STM）和密度泛函理论计算相结合的方法，研究了高纵横比SiNRs上K原子的吸附及其引起的电子性质。由于这些位置的低吸附能，K原子倾向于吸附在双链和多链SiNRs上。每个K原子与其最近的三个硅原子表现出三角形形态，这是由于K和硅原子之间的电荷转移，这一结论得到了理论计算的支持。随着SiNRs上K覆盖度的增加，K原子在SiNRs上组织成一维锯齿形链。此外，发现SiNRs上的K吸附是可逆的。通过STM针尖施加电压脉冲实现了K原子在SiNRs上的沉积，而未损坏SiNRs结构。此外，K吸附有效地调节了SiNRs的狄拉克锥相对于费米能级的位置。本研究揭示了AM原子在SiNRs上的吸附机制，为其他纳米带上的异原子吸附提供了有用的方法。 显示英文摘要

摘要： Silicon nanoribbons (SiNRs), characterized by a pentagonal structure composed of silicon atoms, host one-dimensional (1D) Dirac Fermions and serve as a minimalist atomic template for adsorbing various heteroatoms. Alkali-metal (AM) atoms, such as Na and K, with electronic structures comparable to those of hydrogen are of particular interest for such adsorption studies. However, the adsorption of AM atoms on SiNRs and its tunation on the properties of SiNRs have not yet been fully explored. In this study, we examined the adsorption of K atoms on high-aspect-ratio SiNRs and the resultant electronic properties using a combination of scanning tunneling microscopy (STM) and density functional theory calculations. K atoms prefer to adsorb on double- and multi-stranded SiNRs owing to the low adsorption energies at these sites. Each K atom and its three nearest Si atoms exhibit a triangular morphology resulting from charge transfer between K and Si atoms, as verified by theoretical calculations. As the K coverage of the SiNRs increased, the K atoms organize into 1D zigzag chains on the SiNRs. Moreover, K adsorption on the SiNRs was determined to be reversible. The deposition of K atoms on the SiNRs was achieved using a voltage pulse of the STM tip, without damaging the SiNRs structure. In addition, K adsorption effectively modulates the Dirac cone position of the SiNRs relative to the Fermi level. This study unveils the adsorption mechanism of AM atoms on SiNRs, providing a useful approach for heteroatom adsorption on other nanoribbons.