Fig. 4: Demultiplexing results of OAM beams.

Three demultiplexed conjugated holographic masks for OAM mode spacing of 1, 2 and 3 are obtained from non-collinearly superposed conjugated optical field of MVGBs: \({\sum} {_{l = 3,4,5,6}\widetilde {{{{\mathrm{LG}}}}}_{p = 0}^l\exp \left( {{{{\mathrm{i}}}}2\pi u_lx} \right)}\), \({\sum} {_{l = 3,5,7,9}\widetilde {{{{\mathrm{LG}}}}}_{p = 0}^l\exp \left( {{{{\mathrm{i}}}}2\pi u_lx} \right)}\) and \({\sum} {_{l = 3,6,9,12}\widetilde {{{{\mathrm{LG}}}}}_{p = 0}^l\exp \left( {{{{\mathrm{i}}}}2\pi u_lx} \right)}\). (a₁–a₄), (b₁–b₄) and (c₁–c₄) are experimental intensity profiles of demultiplexed beam components for incident light with one to four collinearly superposed OAM beams with ∆l = 1, ∆l = 2 and ∆l = 3, respectively. (d_1–4) to (f_1–4) are corresponding one dimensional cross-section view of (a_1–4) to (c_1–4), where the insets are the intensity and phase distribution of the corresponding input fields