Topological Pumping of Ultracold Atoms for Quantum Information Science

Quantum information provides a unifying theoretical concept for condensed matter physics, quantum chemistry, information processing, cosmology, and other natural sciences. Processing quantum information is an emerging experimental frontier, but decoherence and scale limit our ability to gain a practical quantum advantage (noisy intermediate-scale quantum, 'NISQ' era). Ultracold atoms in optical lattices exhibit excellent prerequisites for building highly coherent and scalable quantum hardware, as evidenced by their use in optical clocks and atom interferometers. Yet, quantum processing in optical lattices has so far been limited by restricted programmability and qubit connectivity.PumpQIN aims at establishing a universal quantum processing architecture based on topological pumping and controlled collisions between ultracold atoms in optical lattices. A topological pump can be considered a bidirectional, dispersionless, and robustly quantised method for programming atomic motion. Collisions between atoms can thus be configured in time and space, realising coherent two-qubit gates. Milestones of this project include 1) local control over topological pump trajectories, 2) the realisation of a universal quantum processor with motionally coherent bosons, as well as 3) fermionic quantum processing. These objectives will be achieved by constructing a novel quantum gas apparatus with rubidium and potassium atoms.The results of PumpQIN will not only redefine how we think about atoms in optical lattices, but also lead the way towards a 'beyond-NISQ' era. Especially the realisation fermionic processing will establish an interdisciplinary frontier in experimental quantum information science with immediate implications for condensed matter physics and quantum chemistry.