Scanning tunneling spectroscopy of quantum coherence phenomena due to atom-by-atom nanostructure assembly on semiconductor surfaces

联合项目将通过结合两个研究伙伴的专业知识而成为可能。日本方面(NTT基础研究实验室(NTT))在InAs和GaAs基III-V化合物半导体材料的分子束外延(MBE)及其低温扫描隧道谱(STS)表征方面拥有出色的专业知识。NTT运营着全球为数不多的将分子束外延与原位低温扫描隧道显微镜(LT-STM)能力相结合的设施之一。德国的保罗·德鲁德研究所(Paul Drude Institute(PDI))在通过LT-STM和STS表征单个金属对金属纳米结构的原子操纵和STS表征方面拥有杰出的专业知识，目标是通过使用单个吸附原子作为构建块，推动前沿向前发展到半导体表面上单个纳米结构的逐个原子组装。原子操纵的目标适用性--与LT-STM的光谱能力相结合--将代表着在试图理解和控制半导体纳米结构中的电子行为方面的重大进展。这一认识对于未来半导体平台上基于量子结构的器件功能至关重要。在最近的一次联合实验中，我们成功地在InAs衬底上成功地进行了可逆的原子操纵和多功能的纳米结构组装，使我们能够以逐个原子的方式创建和修改纳米结构限制的电子态。据我们所知，这一成果是半导体材料领域的世界性新奇，将标志着该项目的起点。到目前为止，还没有关于利用原子在表面组装的纳米结构来表征和控制基于半导体的量子相干现象的报道。这些事实表明，我们的联合项目将为纳米科技做出开创性的贡献。

The joint project will be made possible by combining the expertise of both research partners. The Japanese side (NTT Basic Research Laboratories (NTT)) has excellent expertise in the field of molecular beam epitaxy (MBE) of InAs and GaAs-based III-V compound semiconductor materials and their characterization by low-temperature scanning tunneling spectroscopy (STS). NTT operates one of the few facilities worldwide which combine MBE with in situ low-temperature scanning tunneling microscopy (LT-STM) capabilities. The German side (Paul Drude Institute (PDI)) has outstanding expertise in the field of atom manipulation by LT-STM and STS characterization of individual metal-on-metal nanostructures assembled one atom at a time.The goal is to push the frontiers forward to the atom-by-atom assembly of individual nanostructures on semiconductor surfaces by using single adatoms as building blocks. The targeted applicability of atom manipulation to semiconductors – in combination with the spectroscopic capabilities of LT-STM – will represent a major advance in the attempt to understand and control electron behavior in semiconductor nanostructures. This understanding is of crucial importance for future device functionality based on quantum structures on semiconductor platform. In a joint experiment, we recently succeeded in reversible atom manipulation and versatile nanostructure assembly on InAs substrates, allowing us to create and to modify nanostructure-confined electronic states in an atom-by-atom fashion. This achievement is – to our knowledge – a worldwide novelty in the field of semiconductor materials and will mark the starting point of the project. Up to now, there is no reported success in the characterization and control of semiconductor-based quantum coherence phenomena utilizing atom-by-atom-assembled nanostructures at surfaces. These facts indicate that our joint project will yield a pioneering contribution to nanometer-scale science and technology.