Tailored orbital angular momentum in high-order harmonic generation with bicircular Laguerre-Gaussian beams

We report on a method to generate extreme ultraviolet vortices from high-order harmonic generation with two-color counter-rotating Laguerre-Gaussian (LG) beams that carry a well-defined orbital angular momentum (OAM). Our calculations show that the OAM of each harmonic can be directly controlled by the OAM of the incident LG modes. Furthermore, we show how the incoming LG modes have to be tailored, in order to generate every possible value of OAM in the emitted harmonics. In addition, we analyze the emitted harmonics with respect to their divergence and find that it decreases with the harmonic order and increases with the OAM of the emitted harmonic.