An on-chip phased array for non-classical light
Volkan Gurses, Samantha I. Davis, Raju Valivarthi, Neil Sinclair, Maria Spiropulu & Ali Hajimiri
Abstract
Quantum science and technology can offer fundamental enhancements in sensing, communications and computing. The expansion from wired to wireless links is an exciting prospect for quantum technologies. For classical technologies, the advent of phased arrays enabled directional and adaptive wireless links by manipulating electromagnetic waves over free space. Here we demonstrate a phased array system on a chip that can receive, image and manipulate non-classical light over free space. We use an integrated photonic-electronic system with more than 1000 functional components on-chip to detect squeezed light. By integrating an array of 32 sub-wavelength engineered metamaterial antennas, we demonstrate a direct free-space-to-chip interface for reconfigurable quantum links. On the same chip, we implement a large-scale array of quantum-limited coherent receivers that can resolve non-classical signals simultaneously across 32 channels. With coherent readout and manipulation of these signals, we demonstrate 32-pixel imaging and spatially configurable reception of squeezed light over free space. Our work advances wireless quantum technologies that could enable practical applications in quantum communications and sensing.
Introduction
The science and engineering of quantum systems have expanded in the last two decades to realize technologies that can manipulate quantum information. Miniaturization and scaling of quantum systems with on-chip integration are crucial to accelerate their use cases toward practical applications. Free-space-interfaced integrated systems enable wireless technologies including free-space sensors, imagers, and communication transceivers. The expansion from wired to wireless links for classical information technologies led to numerous advancements from mobile devices to the Internet-of-Things and facilitated the proliferation of information technologies. For a similar transformation to happen for quantum information technologies, the networking of integrated quantum systems needs to move beyond wired links. [...]