Most, if not all, optical elements, such as lenses, diffraction gratings and phase plates, act on the photon’s position. This talk will describe ways to instead manipulate photons via their transverse momentum, i.e., their angle. I will show that this ‘non-local’ control creates the possibility of completely general spatial optical transformations. I’ll briefly review the use and application of such universal unitary transformations to quantum information and neural networks. I will then introduce our momentum device, which, unlike past universal unitaries implemented in integrated optical systems, works in free space on an array of parallel beams. I will also discuss creating a particularly useful transformation, the transfer-function of free space. By creating nonlocal metamaterial devices, I’ll show that we can compress optical propagation into a thin plate, a device we call a ‘spaceplate’. If perfected, spaceplates could one day replace the space between a lens and the imaging sensor, enabling thin cameras.
This video was produced by the Fields Institute, as part of their Quantum Information Seminar series.
