High-dimensional orbital angular momentum multiplexing nonlinear holography

“Nonlinear holography has been identified as a vital platform for optical multiplexing holographybecause of the appearance of new optical frequencies. However, due to nonlinear wave coupling innonlinear optical processes, the nonlinear harmonic field is coupled with the input field, laying a fundamentalbarrier to independent control of the interacting fields for holography. We propose and experimentallydemonstrate high-dimensional orbital angular momentum (OAM) multiplexing nonlinear holography toovercome this problem. By dividing the wavefront of the fundamental wave into different orthogonal OAMchannels, multiple OAM and polarization-dependent holographic images in both the fundamental wave andsecond-harmonic wave have been reconstructed independently in the spatial frequency domain through atype-II second harmonic generation process. Moreover, this method can be easily extended to cascaded χ2 nonlinear optical processes for multiplexing in more wavelength channels, leading to potential applicationsin multicasting in optical communications, multiwavelength display, multidimensional optical storage, anti-counterfeiting, and optical encryption.”