Generating superimposed Bessel beams with a volume holographic axicon.

Quasi-Bessel beams (QBB) with different profiles are generated with an axicon-telescope system. Beam profiles are found to vary with different axicon-telescope distance δ. QBBs are stored as volume holograms in a photorefractive crystal. Reconstructions of the QBBs are focused by the recording axicon to produce superimposed Bessel beams (SBBs) with oscillating cores. SBBs formed through this method have different oscillation periods that range from 4.3 to 6.1 cm. We demonstrate that periodicity is dependent on δ. Our method allows tunability of the SBB period through a simple rearrangement of optical elements.