Triangular slit interference pattern of single photons with orbital angular momentum: Another beautiful experiment?

This work presents a single-pass diffraction experiment that demonstrates that single photons in a vortex beam in passing through three slits arranged in an equilateral triangle can interfere with themselves and provide quantitative information of their total amount of orbital angular momentum (OAM) they carry. For the experiment presented the aperture has been reduced to a very thin triangular slit. A vortex beam is created by a diffractive optical element (DOE) and then it is made to pass through the slit. This work is considered as an extension to the Young double slit experiment.