Continuously tunable orbital angular momentum generation controlled by input linear polarization.

In this Letter, we theoretically and experimentally demonstrate a new method to generate tunable orbital angular momentum (OAM) by continuously changing the angle of linear polarization of the input light. We use the Fourier series of left- and right-hand projections to prove that the average OAM smoothly varied from l=-1 to l=1 with the angle of LP of input light changing from 0 to π, which is fulfilled by an electrical polarization controller.