School of Physics, The University of New South Wales , Sydney, New South Wales 2052, Australia.
ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, Australian Centre for NanoMedicine, School of Chemistry, The University of New South Wales , Sydney, New South Wales 2052, Australia.
Nano Lett. 2016 Mar 9;16(3):1903-10. doi: 10.1021/acs.nanolett.5b05057. Epub 2016 Feb 10.
We demonstrate that silicon (Si) nanoparticles with scattering properties exhibiting strong dielectric resonances can be successfully manipulated using optical tweezers. The large dielectric constant of Si has a distinct advantage over conventional colloidal nanoparticles in that it leads to enhanced trapping forces without the heating associated with metallic nanoparticles. Further, the spectral features of the trapped nanoparticles provide a unique marker for probing size, shape, orientation and local dielectric environment. We exploit these properties to investigate the trapping dynamics of Si nanoparticles with different dimensions ranging from 50 to 200 nm and aspect ratios between 0.4 and 2. The unique combination of spectral and trapping properties make Si nanoparticles an ideal system for delivering directed nanoscale sensing in a range of potential applications.
我们证明，具有强介电共振散射特性的硅（Si）纳米粒子可以使用光学镊子成功操纵。与传统胶体纳米粒子相比，Si 的大介电常数具有明显的优势，因为它在没有与金属纳米粒子相关的加热的情况下导致增强的捕获力。此外，捕获的纳米粒子的光谱特征为探测尺寸、形状、取向和局部介电环境提供了独特的标记。我们利用这些特性来研究不同尺寸（50nm 到 200nm）和纵横比（0.4 到 2）的 Si 纳米粒子的捕获动力学。光谱和捕获特性的独特组合使 Si 纳米粒子成为在一系列潜在应用中提供定向纳米级传感的理想系统。
