Information encoding in the spatial correlations of entangled twin beams

Abstract

The ability to use the temporal and spatial degrees of freedom of quantum states of light to encode and transmit information is crucial for a robust and efficient quantum network. In particular, the potential offered by the large dimensionality of the spatial degree of freedom remains unfulfilled, as the necessary level of control required to encode information remains elusive. We encode information in the distribution of the spatial correlations of entangled twin beams by taking advantage of their dependence on the angular spectrum of the pump needed for four-wave mixing. We show that the encoded information can only be extracted through joint spatial measurements of the twin beams and not through individual beam measurements and that the temporal quantum correlations are not modified. The ability to engineer the spatial properties of twin beams will enable high-capacity quantum networks and quantum-enhanced spatially resolved sensing and imaging.

Engineering quantum states from a spatially structured quantum eraser

“…As distinguishability is the property one needs to tailor, one may extend our result to other degrees of freedom, such as temporally structured light ( 56 ) as well as multiparticle scenarios ( 57 ). By providing a robust and flexible way to engineer correlations, our scheme could find applications in photonic quantum computation tasks based on multiphoton/multi-interference protocols ( 58 ) or in quantum communication scenarios where users can share images encoded in quantum correlation of a multiphoton state ( 59 ). Last, we believe the structured quantum eraser concept could be beneficial in fields where photon coalescence and structured light are crucial resources such as quantum microscopy, sensing, and metrology.…”