Esseling Michael, Alpmann Christina, Schnelle Jens, Meissner Robert, Denz Cornelia
Institute of Applied Physics, University of Muenster, 48149, Muenster, Germany.
Sci Rep. 2018 Mar 22;8(1):5029. doi: 10.1038/s41598-018-23399-y.
Conical refraction (CR) optical bottle beams for photophoretic trapping of airborne absorbing droplets are introduced and experimentally demonstrated. CR describes the circular split-up of unpolarised light propagating along an optical axis in a biaxial crystal. The diverging and converging cones lend themselves to the construction of optical bottle beams with flexible entry points. The interaction of single inkjet droplets with an open or partly open bottle beam is shown implementing high-speed video microscopy in a dual-view configuration. Perpendicular image planes are visualized on a single camera chip to characterize the integral three-dimensional movement dynamics of droplets. We demonstrate how a partly opened optical bottle transversely confines liquid objects. Furthermore we observe and analyse transverse oscillations of absorbing droplets as they hit the inner walls and simultaneously measure both transverse and axial velocity components.
介绍并通过实验证明了用于光泳捕获空气中吸收性液滴的圆锥折射（CR）光学瓶形光束。CR描述了沿双轴晶体光轴传播的非偏振光的圆形分裂。发散和会聚锥有助于构建具有灵活入口点的光学瓶形光束。通过在双视图配置中实施高速视频显微镜，展示了单个喷墨液滴与开放或部分开放的瓶形光束的相互作用。在单个相机芯片上可视化垂直图像平面，以表征液滴的整体三维运动动力学。我们展示了部分打开的光学瓶如何横向限制液体物体。此外，我们观察并分析了吸收性液滴撞击内壁时的横向振荡，并同时测量横向和轴向速度分量。
