Preparing arbitrary pure states of spatial qudits with a single phase-only spatial light modulator

摘要

Spatial qudits are D-dimensional ($D\geq 2$) quantum systems carryinginformation encoded in the discretized transverse momentum and position ofsingle photons. We present a proof-of-principle demonstration of a method forpreparing arbitrary pure states of such systems by using a single phase-onlyspatial light modulator (SLM). The method relies on the encoding of the complextransmission function corresponding to a given spatial qudit state onto apreset diffraction order of a phase-only grating function addressed at the SLM.Fidelities of preparation above 94% were obtained with this method, which issimpler, less costly, and more efficient than those that require two SLMs forthe same purpose.