Siria Alessandro, Niguès Antoine
Laboratoire de Physique Statistique, Ecole Normale Supérieure, UMR CNRS 8550, PSL Research University, 75005 Paris Cedex 05, Paris, France.
Sci Rep. 2017 Sep 14;7(1):11595. doi: 10.1038/s41598-017-11749-1.
Atomic Force Microscopy (AFM) allows to probe matter at atomic scale by measuring the perturbation of a nanomechanical oscillator induced by near-field interaction forces. The quest to improve sensitivity and resolution of AFM forced the introduction of a new class of resonators with dimensions at the nanometer scale. In this context, nanotubes are the ultimate mechanical oscillators because of their one dimensional nature, small mass and almost perfect crystallinity. Coupled to the possibility of functionalisation, these properties make them the perfect candidates as ultra sensitive, on-demand force sensors. However their dimensions make the measurement of the mechanical properties a challenging task in particular when working in cavity free geometry at ambient temperature. By using a focused electron beam, we show that the mechanical response of nanotubes can be quantitatively measured while approaching to a surface sample. By coupling electron beam detection of individual nanotubes with a custom AFM we image the surface topography of a sample by continuously measuring the mechanical properties of the nanoresonators. The combination of very small size and mass together with the high resolution of the electron beam detection method offers unprecedented opportunities for the development of a new class of nanotube-based scanning force microscopy.
原子力显微镜（AFM）通过测量近场相互作用力引起的纳米机械振荡器的扰动，能够在原子尺度上探测物质。提高AFM灵敏度和分辨率的需求促使引入了一类新型的纳米尺度尺寸的谐振器。在这种背景下，纳米管因其一维特性、小质量和几乎完美的结晶度而成为理想的机械振荡器。再加上功能化的可能性，这些特性使其成为超灵敏、按需力传感器的完美候选者。然而，它们的尺寸使得机械性能的测量成为一项具有挑战性的任务，特别是在室温下无腔几何结构中工作时。通过使用聚焦电子束，我们表明在接近表面样品时可以定量测量纳米管的机械响应。通过将单个纳米管的电子束检测与定制的AFM相结合，我们通过连续测量纳米谐振器的机械性能来成像样品的表面形貌。极小的尺寸和质量与电子束检测方法的高分辨率相结合，为新型基于纳米管的扫描力显微镜的发展提供了前所未有的机遇。
