The holographic optical micro-manipulation system based on counter-propagating beams

We present a system employing a dynamic diffractive optical element to control properties of two counterpropagating beams overlapping within a sample chamber. This system allows us to eliminate optical aberrations along both beam pathways and arbitrarily switch between various numbers of laser beams and their spatial profiles (i.e. Gaussian, Laguerre-Gaussian, Bessel beams, etc.). We successfully tested various counter-propagating dual-beam configurations including optical manipulation of both high and low index particles in water or air, particle delivery in an optical conveyor belt and the formation of colloidal solitons by optical binding. Furthermore, we realized a novel optical mixer created by particles spiraling in counter-propagating interfering optical vortices and a new tool for optical tomography or localized spectroscopy enabling sterile contactless rotation and reorientation of a trapped living cell.