Well, there are things such as Airy beams - https://en.wikipedia.org/wiki/Airy_beam https://en.wikipedia.org/wiki/Airy_beam - I am not sure they fit a helix or

Well, there are things such as Airy beams - https://en.wikipedia.org/wiki/Airy_beam https://en.wikipedia.org/wiki/Airy_beam - I am not sure they fit a helix or disk that well.