Understanding and controlling quantum systems has enabled rapid progress towards quantum technologies – for new information processing, communication, and sensing platforms. At KIT, we investigate quantum phenomena in materials and develop them into building blocks for quantum technologies.

Within MaTeLiS, physicists, chemists, and engineers combine materials synthesis, nanofabrication, spectroscopy, qubit control and theory. Our work spans correlated and topological materials, superconducting circuits, molecular spins, and optical quantum systems. We pursue a variety of research topics:

Understanding quantum matter: Interactions between electrons, spins, and the atomic lattice can produce superconductivity, unusual magnetic order, and other collective quantum states. We study how these states emerge and respond to composition, temperature, magnetic fields, and mechanical strain. Spectroscopic methods, including photon and neutron scattering, reveal their underlying excitations, while theory guides the search for materials with controllable electronic and magnetic properties.

Materials for superconducting quantum circuits: Superconducting circuits store and process quantum information in electrical degrees of freedom controlled by microwaves. We develop novel materials and circuit architectures for qubits, coupling elements, and low-noise readout. For instance, granular aluminum provides a promising platform for high-kinetic-inductance circuits; a KIT-led team demonstrated coherent control and readout of magnetic vortex states in this material in 2026. Studies of microscopic defects, quasiparticles, and unwanted radiation identify limits to coherence and support improved fabrication, shielding, amplification, and signal routing.

Controlling atomic and molecular spins: Atoms and molecules offer quantum states that can be tailored through chemical design and their local environment. We synthesize rare-earth complexes and study electronic and nuclear spins as carriers of quantum information, using electrical and optical readout together with coherent spin control. KIT and collaborators have demonstrated optical initialization and detection of nuclear spin states in a europium-based molecular crystal, with coherence times of up to two milliseconds. Quantum control of individual spins can also be achieved at the single spin level: in 2026, a KIT-led team demonstrated all-electrical coherent control of individual and coupled iron–molecule complexes on surfaces.

Connecting quantum systems with light: Quantum networks require interfaces that transfer information between stationary quantum states and photons travelling through optical fibers. At KIT, we investigate rare-earth molecular systems and diamond color centers coupled to tunable optical microcavities, semiconductor quantum dots, and electrically driven carbon-nanotube emitters. These platforms support single-photon sources, spin–photon interfaces, and quantum memories.

Additionally, a fiber link between Campus North and Campus South provides a testbed for quantum communication. Through the European Superspin project, KIT and its partners aim to connect superconducting qubits with spin-based quantum memories using quantum transducers.

Quantum sensing and control: The sensitivity of quantum states to their environment can be used for precision measurements. We develop superconducting quantum sensors and use spins as local probes of magnetic and electronic environments. Theory contributes models of quantum transport, noise, and open quantum systems. Reservoir engineering supports quantum-state preparation and error correction, while parametric amplifiers enable low-noise detection of weak microwave signals.

The activities in this focus field are part of the topic Quantum materials.

Support from the European Research Council (ERC) enables MaTeLiS researchers to pursue new approaches to quantum hardware, molecular quantum information, quantum sensing, and fundamental physics. Alexey Ustinov’s Milli-Q ERC Advanced Grant develops superconducting quantum circuits for millimeter-wave frequencies up to 100 GHz. Mario Ruben’s Hilbert Molecules ERC Advanced Grant investigates molecular nuclear-spin systems as multilevel quantum-information carriers. Philip Willke’s ATOMQUANT ERC Starting Grant explores quantum coherence in individual atoms and molecules on surfaces through atomic-scale imaging, spin manipulation, and readout. Through the DarkQuantum ERC Synergy Grant, Wolfgang Wernsdorfer and partners develop quantum technologies for searches for axions, hypothetical particles that may account for dark matter.