[addled]

Nice! I worked on something similar as an undergrad project years ago, setting up beams with different orbital angular momentum characteristics. Was a lot fun working in the lab. Sadly I didn’t have the focus/grit to finish writing a paper (sorry Dr. Singh). Side note, this was in 2007 and the folks in our optics lab would check the location of beams by grabbing from the stacks of ancient punchcards lying around and waving them next to the apparatus.

This paper has a pretty similar setup, but adds a spatial light modulator (like a DLP projector that can control phase as well as brightness).

What is wild to me is that the researchers here are able to create a beam where the angular moment changes as you move away.

Plus the really cool spiral patterns.