Characterising the size and shape of metallic nano-structures by their acoustic vibrations
Characterising the size and shape of metallic nano-structures by their acoustic vibrations
复制标题
利用声学振动表征金属纳米结构的大小和形状
DOI：
10.1039/d0nr03410j
复制
发表时间：
2020-07-14
期刊：
影响因子：
6.7
通讯作者：
Clark, Matt
中科院分区：
文献类型：
--
作者：
Fuentes-Dominguez, Rafael;Naznin, Shakila;Clark, Matt
金属纳米结构的表征是非常重要的，因为它们的光学性质强烈依赖于它们的尺寸和形状。在生物成像和传感等应用中，不准确的尺寸或形状表征可能导致误导性测量。通常使用动态光散射、电子显微镜或原子力显微镜等表征技术;然而，在半透明物体内部或液体介质中进行次表面测量非常具有挑战性。在这里，我们使用时间分辨泵浦-探测光谱，通过利用它们的振动模式来测量水周围介质中金属纳米结构的尺寸和形状。我们表明，这种技术可以实现尺寸测量的精度为3 nm的最大的纳米结构，这是在协议与电子显微镜图像。此外，我们证明了探测单个纳米结构的能力，尽管位于相同的光学点扩散函数（PSF）。将该技术提供的高精度和亚光学测量与将金属纳米结构插入生物样品内的能力相结合，可能会开辟一种执行3D表征测量的方法。
The characterisation of metallic nano-structures is of great importance as their optical properties are strongly dependent on their size and shape. Inaccurate size or shape characterisation can result in misleading measurements in applications such as bio-imaging and sensing. Characterisation techniques such as dynamic light scattering, electron microscopy or atomic force microscopy are commonly used; however, performing sub-surface measurements (inside semi-transparent objects) or in liquid media are very challenging. Here, we use time-resolved pump-probe spectroscopy to characterise the size and shape of metallic nano-structures in a water surrounding medium by using their vibrational modes. We show that this technique can achieve size measurements with a precision of 3 nm for the largest nano-structures which are in agreement with electron microscopy images. Furthermore, we demonstrate the ability to probe individual nano-structures despite being located in the same optical point spread function (PSF). Combining the high precision and sub-optical measurements provided by this technique with the ability to insert metallic nano-structures inside biological samples might open a way to perform 3D characterisation measurements.