High-contrast optical vortex detection using the Talbot effect.

We apply the near-field Talbot effect to distinguish, characterize, and detect optical vortices. We perform experiments with single-, double-, multiple-slit, and grating diffraction. High-contrast image detection is achieved with the Talbot effect of a grating, even for higher than l=±1 orbital angular momentum states.

Realization of the single photon Talbot effect with a spatial light modulator.

We demonstrate the quantum Talbot effect using a beam of single photons produced by parametric down conversion. In contrast to the previous works, we use a programmable spatial light modulator to behave as a diffraction grating. Thus, the investigation of the Talbot diffraction patterns under the variation of grating structure can be easily performed.