RAISE-TAQS: Enhancing Classical and Quantum Information Capacities with Imperfect Resources: Experimental Implementations and Theoretical Bounds

University Of Illinois At Urbana-Champaign, Urbana IL

Investigators

Abstract

Quantum channels are the means by which quantum data is transmitted between different locations; they provide the backbone for any quantum communication setup. Quantum channels have many counterintuitive properties with no classical analog. To address problems in quantum communication over realistic channels, we propose an interdisciplinary project that combines the expertise of five researchers in quantum resource theory, advanced photonic quantum information protocols, photonic nonlinear systems, and photonic quantum state characterization and precision optical measurements. Fundamental questions involving quantum entanglement, nonlocality, and causality, are being explored, while translating the theoretical aspects to actual experimental demonstrations. The project investigates the problem of realistic quantum and quantum-enhanced classical information transmission and how their enhanced properties may be applied to near-term computational devices, particularly relevant for engineering, concerned with realistic gains in practical systems. Student development is a primary educational goal of this project. Since the work is largely interdisciplinary, it will provide an opportunity for students from different programs to collaborate in a unique environment. The highly non-classical effects of superadditivity/superactivation and quantum-enhanced two-way communication are two main topical focuses of this project. In the first, two noisy quantum channels become vastly more powerful for communication when used in parallel, and in the second, two-way communication is achieved through the single use of a quantum channel. Experimental validations of these effects will be attained through a team effort involving theorists in math and physics working together with experimentalists from physics and engineering. The theoretical limitations of channel capacities and their behavior in low-dimensional systems will be analyzed, aiming to construct protocols suitable for deployment in tabletop and integrated photonic experiments. Complementing this effort, new experimental techniques are developed using hyper- and hybrid-entangled photons and cavity-enhanced nonlinear effects. Such experimental advances have the potential for powerful application in next-generation photonic quantum information processing. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.