风车液滴：双相水包油液滴的光致旋转
Windmill droplets. Optically induced rotation of biphase oil-in-water droplets
AI总结：
本研究发现光阱中特定结构的双相水包油液滴会产生与光功率成正比的稳定旋转，还可通过序列激活环形光阱间接驱动液滴定向，揭示了非平衡光学操控新现象，为微流控器件及不对称粒子操控研究提供新思路。
摘要：
在微液滴操控领域，光镊已被用于液滴的形成、生长、输运，或是测量液滴对之间的作用力。然而，对光阱中液滴的非平衡现象的探索仍基本处于空白。本文中，我们报道了通过将两种折射率不匹配的不混溶液体（即烃类油和氟碳油）在水中共乳化制备的双相液滴的旋转现象。当被捕获时，具有特定几何结构的液滴会围绕激光束的轴旋转，这似乎是一种耗散性的非平衡现象。通过图像分析得到的旋转频率是稳定的，且与光束功率成正比。值得注意的是，不与捕获光束相互作用的液滴也可以被间接旋转。这一效果通过将液滴放置在由多个依次激活的光阱组成的圆形排列的中心来实现。在这种情况下，液滴会朝向激活光阱的位置定向，其背后的机制尚待阐明。总体而言，我们的研究结果展示了光捕获双相液滴中的非平衡现象，这可为基于这类液滴的器件（例如光致混合等）的开发提供启发。此外，该结果也可能为不对称粒子光学操控的基本原理提供新的认识。
英文摘要：
In the field of microdroplet manipulation, optical tweezers have been used to form and grow droplets, to transport them, or to measure forces between droplet pairs. However, the exploration of out-of-equilibrium phenomena in optically trapped droplets remains largely uncharted. Here, we report the rotation of biphasic droplets fabricated by co-emulsifying two immiscible liquids (i.e., hydrocarbon and fluorocarbon oils) with a refractive index mismatch in water. When trapped, droplets of a specific geometry rotate around the axis of the laser beam, in what appears to be a dissipative, out-of-equilibrium phenomenon. The rotational frequency, obtained from image analysis is stable and proportional to the beam power. Remarkably, droplets that do not interact with the trapping beam can also be rotated indirectly. This is achieved by positioning the droplets at the center of a circular arrangement of multiple, sequentially activated traps. In this case, the droplet orients towards the location of the active trap by a mechanism yet to be understood. Altogether, our results demonstrate out-from-equilibrium phenomenology in optically trapped biphase droplets, which could inspire the development of devices based on them (e.g., optically induced mixing, etc.). In addition, they may shed light on fundamental principles of optical manipulation of asymmetric particles.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
