Complex energy flow structures in tailored light fields for future optical micromanipulation

Since the invention of optical tweezers¹, significant advances have been achieved in optical micromanipulation by introducing structured light fields. These fields are of special interest not only due to their complex intensity structure, but also because of their energy flow²: varying phase distributions go along with orbital angular momentum and energy flow, effecting particle trapping in optical micromanipulation. Beyond that, spatially structuring polarization³ provides neoteric approaches, facilitating the modulation of spin energy flow. We demonstrate the realization and investigation of customized orbital and spin energy flow structures exceeding the actual stage of basic studies. Based on higher-order Gaussian modes, we apply tailored orbital flow to realize sophisticated spin structures. We analyze flow dynamics depending on mode numbers, thereby establishing a connection between topological charge and resulting spin structures. Novel topologies are developed embedding stationary points in their flow, paving the way to advanced optical manipulation. ¹Ashkin A et al. 1986 Opt.Lett. 11 288 ²Kumar V et al. 2014 J.Opt. Soc. Am. B 31 A40 ³Otte E et al. 2016 J.Opt. 18 074012