论文标题
探测单纳米颗粒与光学镊子的光学手性反应
Probing the optical chiral response of single nanoparticles with optical tweezers
论文作者
论文摘要
我们提出了一种使用光学镊子对均相性手性颗粒进行分类的对映选择性方案。对于一定范围的材料参数，我们表明，高度聚焦的圆形激光束捕获了由诱捕束的握手选择的特定手性的颗粒。此外，通过施加横向stokes拖曳力来移位被捕获的粒子离轴，我们允许围绕捕获梁轴的粒子中心质量旋转。旋转角度高度取决于被困粒子的触手可及，并且可以通过标准的视频微观镜技术易于测量，从而提供了手性分辨率的替代机制。我们的平台不仅允许对溶液中分散的颗粒进行对映射，而且还铺平了使用光学镊子来表征单个均质性手性微球的手性参数的方式。
We propose an enantioselective scheme to sort homogeneous chiral particles using optical tweezers. For a certain range of material parameters, we show that a highly focused circularly-polarized laser beam traps particles of a specific chirality selected by the handedness of the trapping beam. Furthermore, by applying a transverse Stokes drag force that displaces the trapped particle off-axis, we allow for the rotation of the particle center-of-mass around the trapping beam axis. The rotation angle is highly dependent on the handedness of the trapped particle and is easily measurable with standard video-microscopy techniques, allowing for an alternative mechanism for chiral resolution. Our platform not only allows for enantioselection of particles dispersed in solution but also paves the way to the characterization of the chiral parameter of individual, homogeneous chiral microspheres using optical tweezing.
