Dynamics of the depletion zone at a finite-sized imperfect trap in two dimensions: Photobleaching experiments and simulations

The kinetics of the growth of depletion zones around a static trap in an effective two-dimensional geometry were analyzed. The photobleaching of fluorescein dye by a focused laser beam was used for the investigation. It was shown that both the imperfect trapping strength and the finite trap size controlled the early-time behavior, while the trap shape does not much affect the dynamics of the θ distance. For different laser powers of the phototrap, the actual trapping efficiency was determined.