Generation of uniform intensity diffraction-free tubular light beams using a logarithmic axicon and a vortex phase plate

We propose and demonstrate a scheme for producing high-order Bessel-type diffraction-free beams of uniform intensity within a set range along the optical axis by illuminating a logarithmic axicon with a vortex phase plate-generated light beam. This results in hollow or tubular constant intensity light beams whose diameter depends on the vortex topological order. To the best of our knowledge, this is the first realization of the homogenization of tubular non-diffracting beams. The technique can find applications in microscopy, particle and atom manipulation/trapping, and laser ablation or micro-machining.