Manipulating spatial qudit states with programmable optical devices

G. Lima, A. Vargas, L. Neves, R. Guzmán and C. Saavedra
OPTICS EXPRESS 17, 13 (2009)


The study of how to generate high-dimensional quantum states (qudits)
is justified by the advantages that they can bring for the field of
quantum information. However, to have some real practical potential for
quantum communication, these states must be also of simple
manipulation. Spatial qudits states, which are generated by engineering
the transverse momentum of the parametric down-converted photons, have
been until now considered of hard manipulation. Nevertheless, we show
in this work a simple technique for modifying these states. This
technique is based on the use of programmable diffractive optical
devices, that can act as spatial light modulators, to define the
Hilbert space of these photons instead of pre-fabricated multi-slits.