Abstract:
Nanowelding is a bottom-up technique to create custom-designed nanostructures and devices beyond the precision of lithographic methods. Here, a new technique is reported based on anisotropic lubricity at the van der Waals interface between monolayer and bilayer SnSe nanoplates and a graphene substrate to achieve precise control of the crystal orientation and the interface during the welding process. As-grown SnSe monolayer and bilayer nanoplates are commensurate with graphene\'s armchair direction but lack commensuration along graphene\'s zigzag direction, resulting in a reduced friction along that direction and a rail-like, 1D movement that permits joining nanoplates with high precision. This way, molecular beam epitaxially grown SnSe nanoplates of lateral sizes 30-100 nm are manipulated by the tip of a scanning tunneling microscope at room temperature. In situ annealing is applied afterward to weld contacting nanoplates without atomic defects at the interface. This technique can be generalized to any van der Waals interfaces with anisotropic lubricity and is highly promising for the construction of complex quantum devices, such as field effect transistors, quantum interference devices, lateral tunneling junctions, and solid-state qubits.
摘要:
Nanowelding是一种自下而上的技术,用于创建超出光刻方法精度的定制设计的纳米结构和器件。这里,报道了一种新技术,该技术基于单层和双层SnSe纳米片与石墨烯衬底之间的范德华界面处的各向异性润滑性,以在焊接过程中实现对晶体取向和界面的精确控制。生长的SnSe单层和双层纳米板与石墨烯的扶手椅方向相称,但缺乏沿石墨烯的之字形方向的相称性,导致沿着该方向的摩擦减少和类似于轨道的,1D运动,允许以高精度连接纳米板。这边,在室温下,通过扫描隧道显微镜的尖端操纵横向尺寸为30-100nm的分子束外延生长的SnSe纳米片。随后将原位退火应用于与纳米板接触的焊缝,而在界面处没有原子缺陷。该技术可以推广到具有各向异性润滑性的任何范德华界面,并且对于构建复杂的量子器件非常有希望,如场效应晶体管,量子干涉器件,横向隧道结,和固态量子比特。