A procedure to efficiently sort orbital angular momentum (OAM) states of light, by performing a Cartesian to log-polar coordinate transformation which translates helically phased beams into a transverse phase gradient, currently exists1. We implement this mode transformer, which comprises of two custom refractive optical elements2, to efficiently sort Bessel beams carrying OAM. Introducing two cylindrical lenses, allows the focusing of each of the input OAM Bessel states to a different lateral position in the Fourier plane and separates the radial wave-vectors in the image-plane. We demonstrate the concept by separating over forty OAM states and radial wave-vectors.
Reference:
Mhlanga, T, Dudley, A.L., McDonald, A, Roux, F.S, Lavery, M, Padgett, M and Forbes, A, “Efficient sorting of Bessel beams” Complex Light and Optical Forces VII, Jesper Glückstad, David L. Andrews, Enrique J. Galvez, Editors, Proc. of SPIE Vol. 8637, 86371C (2013)
Mhlanga, T., Dudley, A. L., McDonald, A., Roux, F., Lavery, M., Padgett, M., & Forbes, A. (2013). Efficient sorting of Bessel beams [Conference paper]. SPIE Digital llibrary. http://hdl.handle.net/10204/6774
Mhlanga, T, Angela L Dudley, A McDonald, FS Roux, M Lavery, M Padgett, and A Forbes. "Efficient sorting of Bessel beams [Conference paper]." (2013): http://hdl.handle.net/10204/6774
Mhlanga T, Dudley AL, McDonald A, Roux F, Lavery M, Padgett M, et al, Efficient sorting of Bessel beams [Conference paper]; SPIE Digital llibrary; 2013. http://hdl.handle.net/10204/6774 .
