Dynamic shaping of colloidal particles into the beam patterns
The degree of freedom of applicability of optical tweezers often driven by Gaussian profile was restricted as well as non-dynamic in nature. For simultaneous multiple particle trapping, we need to generate multiple tight focused intensity spots which are often achieved by modulating the laser beam spatially. In this context, we have generated experimentally the structured beams of geometry similar to the shape of number 3, spiral, and circle, respectively. In our case, each point of the transverse profiles of the structured beams works as an optical tweezers, resulting as multiple optical tweezers (MOTs). The MOTs are demonstrated for simultaneous multiple trapping of polystyrene beads of two different sizes such as 1 μm and 4.5 μm in diameter. The transverse organization of these structured light fields is transferred to corresponding geometry of polystyrene beads. The
present approach eliminates most of the inherent limitations of other existing schemes and set a new trend of multi-particles trapping.