Photonic integrated processor for structured light detection and distinction
Johannes Bütow, V. Sharma, Dorian Brandmüller, Jörg S. Eismann, Peter Banzer
Abstract
Abstract Integrated photonic devices are pivotal elements across research fields that involve light-based applications. Particularly versatile platforms are programmable photonic integrated processors, which are employed in applications like communication or photonic computing. Free-space distributions of light can be coupled to such processors, which subsequently control the coupled light on-chip within meshes of programmable optical gates. This enables access to the spatial properties of free-space light, particularly its relative phase, which is usually challenging to measure. Here, we discuss and show the detection of amplitude and phase distributions of structured higher-order light beams using a multipurpose photonic processor. This can be used to directly distinguish light’s orbital angular momentum without including additional elements interacting with the free-space light. We envision applications in a range of fields that rely on the spatial distributions of light’s properties, such as microscopy or communications.