This article reports on energy-dispersive micro Laue (µLaue) diffraction of an individual gold nanowire that was mechanically deformed in three-point bending geometry using an atomic force microscope. The nanowire deformation was investigated by scanning the focused polychromatic X-ray beam along the nanowire and recording µLaue diffraction patterns using an energy-sensitive pnCCD detector that permits measurement of the angular positions of the Laue spots and the energies of the diffracted X-rays simultaneously. The plastic deformation of the nanowire was shown by a bending of up to 3.0 ± 0.1°, a torsion of up to 0.3 ± 0.1° and a maximum deformation depth of 80 ± 5 nm close to the position where the mechanical load was applied. In addition, extended Laue spots in the vicinity of one of the clamping points indicated the storage of geometrically necessary dislocations with a density of 7.5 × 1013 m−2. While µLaue diffraction with a non-energy-sensitive detector only gives access to the deviatoric strain, the energy sensitivity of the employed pnCCD offers absolute strain measurements with a resolution of 1%. Here, the residual strain after complete unloading of the nanowire amounted to maximum tensile and compressive strains of the order of +1.2 and −3%, which is comparable to the actual resolution limit. The combination of white-beam µLaue diffraction using an energy-sensitive pixel detector with nano-mechanical testing opens up new possibilities for the study of mechanical behavior at the nanoscale.

中文翻译：

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弯曲金纳米线上的能量色散 X 射线微劳厄衍射

本文报道了使用原子力显微镜在三点弯曲几何结构中机械变形的单个金纳米线的能量色散微劳厄 (μLaue) 衍射。通过沿纳米线扫描聚焦的多色 X 射线束并使用能量敏感的 pnCCD 探测器记录 µLaue 衍射图案来研究纳米线变形，该探测器允许同时测量 Laue 斑点的角位置和衍射 X 射线的能量。纳米线的塑性变形表现为在靠近施加机械载荷的位置处弯曲高达3.0±0.1°，扭转高达0.3±0.1°，最大变形深度为80±5nm。此外，在一个夹紧点附近延伸的劳厄点表明存储了密度为 7.5 × 1013 m−2 的几何必要位错。虽然使用非能量敏感探测器的 µLaue 衍射只能获取偏应变，但所用 pnCCD 的能量灵敏度可提供分辨率为 1% 的绝对应变测量。在这里，纳米线完全卸载后的残余应变达到+1.2%和-3%量级的最大拉伸和压缩应变，这与实际分辨率极限相当。使用能量敏感像素探测器的白束 µLaue 衍射与纳米机械测试的结合为纳米尺度机械行为的研究开辟了新的可能性。