The use of quantum correlations between spatial modes of light for enhanced information processing and metrology is a relatively unexplored frontier. Additionally, engineering the spatial properties of quantum-optical states is crucial for realizing emerging applications in quantum communication, quantum imaging/sensing. By harnessing the infinite dimensionality of the Hilbert space of spatial degrees of freedom, information can be encoded and transmitted via the spatially multimode properties of twin beams. In this talk, I will present our recent results on tailored information encoding in the form of the relative momentum distribution of photons in entangled twin beams. By suitably modifying the angular spectrum of the input pump for a non-linear multimode process of four-wave mixing, we show that complete control of spatial properties of output twin beams is possible. Furthermore, accessing the encoded information requires making joint spatial measurements of the twin beams, which provides security against eavesdropping. While the experiment represents a proof-of-principle demonstration, our results conclusively prove the ability to engineer the spatial properties of twin beams, which will enable high-capacity quantum networks and quantum-enhanced spatially resolved sensing and imaging applications in the future.
Host: Jack Harris (jack.harris@yale.edu)