QuIC-TAQS: Implementation of a Neutral-Atom-Photonic-Cluster State

University Of Oregon Eugene, Eugene OR

Investigators

Abstract

Quantum information science and technology (QIST) holds promise to transform radically our technological landscape by developing new computational, communications and sensing modalities as identified in the National Quantum Initiative. The potential long-term impacts on national needs of QIST are diverse and include enhancing scientific progress as well as economic and national security. Quantum Interconnects (QuICs), which enable transferring quantum information between different physical systems, are an essential class of components needed for the realization of QIST. The team will develop and demonstrate a novel interface between neutral atoms and photons, or light ‘particles’. Our approach is based on generating a correlated system of atoms and photons, known as a cluster state, that can be used for quantum computation, sensing and communications. By utilizing an integrated-optics (on-chip) platform to manipulate photons at telecommunications wavelengths, the PI and his collaborators aim to develop a system that can be readily deployed in quantum network applications. The impacts on basic science and engineering will be significant. For example, our work enables new ways to create and control large quantum systems, which could provide new approaches to simulate nature. This project contributes to a diverse quantum-ready workforce through training of graduate and undergraduate students and range of outreach activities. To produce neutral-atom-photonic cluster states this project combines the deterministic generation of primitive photonic cluster states via light single-atom emission with an integrated-optics platform. All-optical operations will be implemented on-chip to combine (‘fuse’) the primitive cluster states into larger ones that can serve for quantum information processing and enable overcoming loss in a quantum network. Specifically,the primitive photonic cluster states are generated by photon emission from single neutral rubidium atoms that are laser-trapped and strongly coupled to separate optical cavities defined in a common nanophotonic-crystal waveguide fabricated in silicon nitride. Laser and microwave controls cause the atom(s) to emit deterministically a sequence of single-photon wave packets that propagate along the waveguide axis. The photons carry information about the atomic state in their emission time. Photons can occupy a superposition of these ‘time bins’, corresponding to a time-bin quantum bit (‘qubit’). The photons are coupled into an external integrated-optics chip containing fast switches for combining the photon packets with appropriate delays designed for photonic ‘fusion gate’ operations, which are implemented by detecting a subset of photon outputs from the chip. 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.