Ussembayev Yera, Arakawa Yuki, Beunis Filip, Spoelstra Anne B, Bus Tom, Schenning Albert P H J, Neyts Kristiaan
LCP Research Group, Ghent University, Technologiepark 126, Gent 9052, Belgium.
Center for Nano and Biophotonics, Ghent University, Technologiepark 126, Gent 9052, Belgium.
ACS Nano. 2025 Aug 12;19(31):28460-28468. doi: 10.1021/acsnano.5c07197. Epub 2025 Jul 18.
Precise manipulation of microscopic objects is crucial for applications in biomedicine, robotics, and nanotechnology. However, achieving stable trapping, controlled release, and rapid propulsion with a single laser beam remains a significant challenge. Here, we elucidate the optical forces and torques exerted on chiral liquid crystal polymer microparticles when the laser wavelength is within their photonic bandgap and demonstrate the application in an optical blaster. Photons with polarization handedness opposite that of the chiral helical structure in the particle are transmitted and can be used to trap the particle, while photons with the same polarization handedness lead to a strong recoil effect. By leveraging this mechanism, we create an optical blaster that first loads the microparticles into the optical trap and subsequently launches them as microrockets by switching the circular polarization handedness of the light beam. The particles achieve propulsion speeds up to 234 μm s and finally levitate well above the laser focus after a balance between gravity and the optical force is reached. The optical blaster concept holds promise for diverse applications in ultrafast cargo transport, soft microrobots, microsurgery, and the advanced nanomanipulation of small objects.
对微观物体进行精确操控对于生物医学、机器人技术和纳米技术等领域的应用至关重要。然而，利用单一激光束实现稳定捕获、可控释放和快速推进仍然是一项重大挑战。在此，我们阐明了当激光波长处于手性液晶聚合物微粒的光子带隙内时施加在其上的光学力和扭矩，并展示了在光学发射器中的应用。与微粒中手性螺旋结构偏振方向相反的光子会透射，并可用于捕获微粒，而具有相同偏振方向的光子则会产生强烈的反冲效应。通过利用这一机制，我们制造了一种光学发射器，它首先将微粒加载到光学陷阱中，随后通过切换光束的圆偏振方向将它们作为微型火箭发射出去。微粒的推进速度可达234μm/s，在重力与光学力达到平衡后最终悬浮在激光焦点上方很远的位置。光学发射器概念在超快货物运输、软微型机器人、显微手术以及小物体的先进纳米操纵等多种应用中具有广阔前景。
