Digital bi-photon spiral imaging

Quantum ghost imaging using entangled photon pairs has become an interesting field of investigation as it illustrates the quantum correlation between the photon pairs. We introduce a new technique using spatial light modulators encoded with appropriate digital holograms to recover not only the amplitude, but also the phase of the digital object. Down-converted photon pairs are entangled in the orbital angular momentum basis, which are typically measured using a spiral phase hologram. Thus by encoding a spiral annular slit hologram into the idler arm, and varying it radially we can simultaneously recover the phase and amplitude of the field in question. We show that there is a good correlation between the encoded field function and the reconstructed images.