Continuous yaw (in-plane) rotation of an optically trapped birefringent particle is conventionally achieved by illuminating with light of high ellipticity. This ellipticity has to be high enough to make the tilt of the washboard potential bypass the confining effect of the corrugation. Here by using a novel technique, we generate continuous rotations of a 3 m sized spherical birefringent particle with ellipticity lower than that permissible with a single optical tweezers beam. We use two lasers, near-orthogonally polarized, with similar intensities at wavelengths of 1064 and 975 nm to obtain continuous rotations, just by making one of the beams elliptically polarized, but well lower than that permissible by the washboard potential. The maximum rotation frequency we achieve with the present configuration is 5 Hz which can be increased by simultaneously increasing the two laser intensities.

光学捕获的双折射粒子的连续偏航（平面内）旋转通常是通过用高椭圆率的光照射来实现的。该椭圆度必须足够高，以使搓衣板电位的倾斜绕过波纹的限制效应。在这里，通过使用一种新技术，我们生成了 3m 大小的球形双折射粒子，其椭圆度低于单光镊光束允许的椭圆度。我们使用两个近正交偏振的激光，在 1064 和 975 nm 的波长下具有相似的强度来获得连续旋转，只需使其中一个光束椭圆偏振，但远低于搓板电位允许的值。我们使用当前配置实现的最大旋转频率为 5 Hz，可以通过同时增加两种激光强度来增加。