Optical levitation

In optical levitation, a focused, vertically aligned laser beam is used to trap micrometer sized where the photon pressure from the light is balancing gravity. I will in this work review the field by presenting a number of different experiments. I will show how the Foerster Resonance Energy Transfer (FRET) mechanism can be used to track the dynamics of two coalescing glycerol droplets. Second, I will show the directional Mie spectrum of evaporating water droplets arrange in consecutive Fano Combs. This observation is explained by a quantum analogy where the droplet can be seen as an "optical atom" with angular momentum, tunneling, and excited states. Third, I will show how we have used optical levitation to create a single droplet version of Millikan's experiment where the effects of a single electron removal can be observed by the naked eye and measured with a ruler. Finally, I will present our ongoing efforts to trap nanometer sized particles in vacuum and a method to levitate metallic particles.