QSE Quantum Seminar, "Topological pumping and quantum information processing" - Konrad Viebahn

Please join us for the QSE Center Quantum Seminar with Konrad Viebahn from ETH Zurich who will give the talk "Topological pumping and quantum information processing" on Thursday October 23 from 12pm to 1:30pm
Location: CE 1 105

Pizzas will be available between the seminars at 12:00. All PhDs, postdocs, students, group leaders, and PIs are welcome to join us.

TITLE: "Topological pumping and quantum information processing"

ABSTRACT:
Topological pumps provide a powerful method for transporting particles with remarkable precision by slowly and cyclically modulating a lattice potential. This transport is topologically protected - a feature it shares with the quantum Hall effect - making it inherently robust against noise and experimental imperfections.
In this colloquium, I will introduce a novel paradigm of this concept: moving beyond the transport of individual particles to the pumping of qubits carrying quantum information. Our experiments, which employ ultracold fermions in dynamical optical lattices [1,2], demonstrate the coherent transport of not only single atoms but also entangled Bell pairs over hundreds of lattice sites. This capability allows us to perform fundamental quantum computations during transport, including high-fidelity two-qubit gates. I will show how we can chain these operations together to build non-local quantum circuits and generate complex entanglement patterns across the lattice.

[1] arXiv:2409.02984 “Splitting and connecting singlets in atomic quantum circuits”
[2] arXiv:2507.22112 “Protected quantum gates using qubit doublons in dynamical optical lattices”

BIO: 
Having studied at LMU Munich and at the University of Cambridge, Konrad did his PhD at the University of Cambridge, where he set up a laboratory for studying ultracold atoms in quasicrystals made of light. In 2018 he moved to ETH Zurich, first as an ETH Fellow, and later as a junior group leader in the lab of Tilman Esslinger. His research explores the frontiers of topological matter, many-body physics, and quantum information, using ultracold fermions in dynamically tuneable optical lattices.