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arXiv 2111.12901cond-mat.mtrl-scicond-mat.mes-hall
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二维材料表面层状薄板的原子尺度应变工程

Atomic scale strain engineering of layered sheets on the surfaces of two-dimensional materials

N. Sarkar, P. R. Bandaru, R. C. Dynes

摘要:

利用扫描隧道显微镜(STM)针尖诱导力对二维材料进行原子调制,可以改变材料的力学和电学性质。通过电隧穿的原位地形和光谱探测已被用于应变片的石墨,单层石墨烯和NbSe 2。这一发现也解决了一个长达35年的争议,这个争议涉及到许多提出的模型,这些模型解释了石墨表面原子振动产生的异常高的测量原子振幅(高达24埃,预计为0.2埃)的来源。我们的研究结果属性的异常,表面弹性形变特性的软二维单原子片的石墨烯和石墨相比,NbSe 2,这是与他们的本地键合配置。研究表明,针尖诱导变形可以在材料表面原子级地诱导可控应变,为应变工程提供了一种新的途径。所形成的石墨莫尔图案的地形变形揭示了层间范德华(vdW)强度在其域中变化。原位隧道光谱与应变的莫尔域揭示电子平带形成可控,从而创建一个平台,多体相关性。本文警告异常的观察时,探测二维材料在小间隙距离与其应变诱导效应,并提供指导方针,以利用或避免这种影响。

英文摘要:

Atomic modulations of two-dimensional materials using scanning tunneling microscope (STM) tip-induced forces modifies their mechanical and electrical properties. In situ topographic and spectroscopic probing through electrical tunneling has been used for straining sheets of graphite, monolayer graphene and NbSe2. The findings also resolve a thirty-five-year-old controversy involving numerous proposed models to explain the source of anomalously high measured atomic amplitudes (of up to 24 Angstroms, expected 0.2 Angstroms) from atomic corrugation on graphite surfaces. Our findings attributes the anomaly to surface elastic deformation characteristics of soft 2D monatomic sheets of graphene and graphite in contrast to NbSe2 which is associated with their local bonding configurations. The tip-induced deformations are shown to induce controlled strain on the material surface atomically and it offers a new way for strain engineering. Topographic deformation of formed graphitic Moire patterns reveals the inter-layer van der Waals (vdW) strength varying across its domains. In-situ tunneling spectroscopy associated with straining of the Moire domains reveals electronic flat band formation controllably thereby creating a platform for many-body correlations. The paper cautions anomalous observations when probing 2D materials at small gap distances with their strain induced effects and provides guidelines to exploit or avoid this effect.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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