Substrate-supported atomic-scale In nanowires:Structure, phase transition and spectroscopic properties

拟议的联合理论-实验项目旨在从光谱特征中提取对Si（111）上原型In纳米线的更深入理解。除了基态结构，吸附原子和缺陷对金属-绝缘体相变的影响将通过将非接触表面光谱与基于密度泛函理论（DFT）的第一性原理计算相结合来探索。与光学光谱到远红外（FIR）以及拉曼光谱，我们测量电子激发由于带间和带内跃迁以及表面振动。所测量的光谱指纹与计算的签名的比较允许探测结构候选人，并预计导致纳米线的几何形状和电子性质之间的关系的透彻理解。此外，计算将有助于合理化的热力学和驱动力的temperatureinduced相变，并将被用来与兰道尔电导的纳米线，其结构特性和外部修改。

The proposed joint theoretical-experimental project aims to extract a deeper understanding of the prototypical In nanowires on Si(111) from spectroscopic signatures. In addition to the ground-state structure, the impact of adatoms and defects on the metal-insulator phase transition will be explored by combining non-contact surface optical spectroscopy with first-principles calculations based on density-functional theory (DFT). With optical spectroscopy into the far infrared (FIR) as well as Raman spectropscopy we measure electronic excitations due to inter- and intraband transitions as well as surface vibrations. The comparison of the measured spectroscopic fingerprints with calculated signatures allows for probing structural candidates and is expected to lead to a thorough understanding of the relation between the nanowire geometry and electronic properties. Furthermore, the calculations will help to rationalise the energetics and driving forces of the temperatureinduced phase transition and will be used to relate the Landauer conductance of the nanowires to their structural properties and external modifications.