Autor: |
Rode, Johannes C., Zhai, Dawei, Belke, Christopher, Hong, Sung J., Schmidt, Hennrik, Sandler, Nancy, Haug, Rolf J. |
Rok vydání: |
2019 |
Předmět: |
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Zdroj: |
2D Mater. 6, 015021 (2019) |
Druh dokumentu: |
Working Paper |
DOI: |
10.1088/2053-1583/aaf1e7 |
Popis: |
Thin adhesive films can be removed from substrates, torn, and folded in distinct geometries under external driving forces. In two-dimensional materials, however, these processes can be self-driven as shown in previous studies on folded twisted bilayer graphene nanoribbons produced by spontaneous tearing and peeling from a substrate. Here, we use atomic force microscopy techniques to generate and characterize the geometrical structure of naturally self-grown folded nanoribbon structures. Measurements of nanoribbon width and interlayer separation reveal similar twist-angle dependences possibly caused by the anisotropy in the bilayer potential. In addition, analysis of the data shows an unexpected correlation between the height of the folded arc edge -parameterized by a radius R-, and the ribbon width, suggestive of a self-growth process driven by a variable cross-sectional shape. These observations are well described by an energy minimization model that includes the bilayer adhesion energy density as represented by a distance dependent Morse potential. We obtain an analytical expression for the radius R versus the ribbon width that predicts a renormalized bending rigidity and stands in good agreement with experimental observations. The newly found relation between these geometrical parameters suggests a mechanism for tailored growth of folded twisted bilayer graphene -- a platform for many intriguing physics phenomena. |
Databáze: |
arXiv |
Externí odkaz: |
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