EAGER: Quantum Manufacturing "Scalable integration of ion-photon quantum information converters (IP-QIC) on fiber for networking and computing applications

This grant will support research advancing the precision manufacturing of fiber optic cables housing integrated quantum ionic processors for future applications in a scalable network. To create such a network, existing state-of-the-art information-processing quantum hardware, such as ionic processors, must be accompanied by developing adequate interconnects to allow the scalable integration of multiple processors as nodes in the more extensive cooperative network.

For this integration, fiber optics, the workhorse of digital communication, needs to undergo a quantum-enabling transformation. This grant will pursue the manufacturing of custom fiber that is capable of lossless translation of quantum-coherent information from the stationary form encoded on the ionic qubit processor into the flying qubits transmitted by photons through the communication links and vice versa.

This research will deliver the optimized design for scalable manufacturing of a new class of fibers, in which linear ion arrays are integral sections of the fiber light-guiding core. Such a contiguous integration of the stationary-qubit processors into the optical path of the flying-qubit streamline will enable the unification of isolated processors into a synchronized network capable of performing information processing tasks of a respectively scaled-up complexity.

The project's educational component will focus on outreach to attract underrepresented groups to pursue education in Quantum Information Science and launch the internship program in Quantum Manufacturing in industries focused on rekindling domestic manufacturing.

The grant will advance the manufacturing engineering research of a high-fidelity Ionic-Photonic Quantum Information Converter (IP-QIC) integrating ionic processors into a scalable quantum network. It will explore the theory-to-practice optimization of the fabrication of fiber-optic systems in which arrays of trapped ions replace sections of optically guiding core.

Combining a thermal draw of fiber, in which a quadrupole of electrodes is concentric to the optical core, followed by selective etching of axial gaps in the fiber cladding, and controlled reflow by a capillary instability of the resulting gap-edges into micro-lenses, a fiber system in which multiple Paul traps can be house axially along the fiber will be fabricated. The Paul traps will be loaded in Ultra-High Vacuum (UHV) with linear ion arrays concentrically aligned with the optical cores of the fiber, integrating them into a single quantum-coherent system.

The fiber-optic theory claims no cut-off for the fundamental guided optical mode for any cylindrically symmetric system of refractive index higher than its environment, such as that of a linear ion array in a vacuum. Thus, a fiber system in which the ion arrays are the integral sections of the optical core, forming an uninterrupted, continuous lightguide, is possible.

Such a seamless arrangement is expected to boost interaction efficiency between the photonic and ionic qubits, resulting in a conversion of quantum information back and forth between those two physical forms. The project will classify the cutting-edge fiber manufacturing approaches for precision in materializing the quantum-information systems of increasing complexity.

IP-QIC is a novel physical arrangement that opens for experimental investigation hitherto unexplored correlation terms in the overall Hamiltonian of the system, describing the coupling of the fiber's optical modes to the ion array's phononic and excitonic states. Thus, IP-QIC will open a niche in quantum algorithmics, exploring the behavior of complex quantum matter, such as strongly correlated and topological, as well as data routing protocols for robust and extensible software-defined quantum networks.

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.