EXC 2004:  Matter and Light for Quantum Computing (ML4Q)

• Subject Area: Condensed Matter Physics ; Optics, Quantum Optics and Physics of Atoms, Molecules and Plasmas
• Term: since 2019
• Website: Homepage
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 390534769

After decades of rapid developments, computer hardware is facing fundamental limits of microfabrication, while the demand for information technologies keeps increasing. Clearly, solutions for the next information age are required. There is growing optimism that quantum information technology may play a key role in this development. Computing and networking power beyond anything classically imaginable would make quantum machines powerful tools in key areas such as communication or the design of materials and chemicals. Investments by major enterprises including Microsoft, IBM, Intel, and Google as well as by China, Canada, and the EU testify to the concreteness of the development process. At this stage, the technologies for creating fragile quantum bits ('qubits') are reaching maturity, and viable concepts to protect quantum information from disturbances are being developed. This progress is owed to largely independent efforts in the research fields of quantum materials, quantum optics, and quantum information science.The time has now come to take the first steps to unify three concepts developed in these fields: topologically protected qubits, optically linked quantum entanglement, and error-correcting codes. This will lay the foundation for versatile quantum information technologies capable of both computing and networking. Based on this paradigm, we will establish a synergetic collaboration of top researchers working in the respective fields at the universities of Cologne, Bonn, and Aachen, as well as at the Research Center Jülich. This will lead to an internationally highly visible consortium for research on quantum information technologies in Germany. Its characteristic combination of topological matter, light, and quantum information science is unique and provides a highly promising basis for quantum information technology.Our long-term goal is the realization of architectures consisting of optically-networked, fault-tolerant quantum computing modules. Emphasis in the first years will be put on basic research, organized in four focus areas. F1: Fundamentals and technology for topological interfaces will seek optimized ways to realize 'Majorana states' – potent carriers of quantum information – in topological phases of both condensed matter and cold atoms. F2: Majorana qubits aims to develop qubits based on these states. F3: Decoherence, measurements, and error correction will develop novel concepts and schemes for the protection of quantum information. F4: Quantum connectivity will realize links between different types of qubits and develop quantum networking protocols.We will achieve our objectives through close collaboration between different fields of physics and via the strategic installment of new professorships and various support facilities. A new research school encompassing the three universities will provide the infrastructure for training the next generation of scientists in the field.

• DFG Programme: Clusters of Excellence (ExStra)
• Applicant Institution: Universität zu Köln
• Co-Applicant Institution: Rheinisch-Westfälische Technische Hochschule Aachen; Rheinische Friedrich-Wilhelms-Universität Bonn
• Participating Institution: Forschungszentrum Jülich
• Participating University: Heinrich-Heine-Universität Düsseldorf
• Spokesperson: Professor Dr. Yoichi Ando
• Participating Researchers: Professor Dr. Alexander Altland; Professor Dr. Hendrik Bluhm; Professor Dr. Stefan Blügel; Professorin Dr. Dagmar Bruß; Professor Dr. Tommaso Calarco; Professor Dr. David DiVincenzo; Professor Dr. Sebastian Diehl; Professor Dr. Reinhold Egger; Professor David Gross, Ph.D.; Professor Dr. Alexander Grüneis; Professor Dr. Detlev Grützmacher; Professor Dr. Fabian Hassler; Professorin Dr. Beata Kardynal; Dr. Michael Kastoryano; Professor Dr. Joachim Knoch; Professorin Dr. Corinna Kollath; Professor Dr. Michael Köhl; Professor Dr. Stefan Linden; Professorin Grace Lu, Ph.D.; Professor Dr. Dieter Meschede; Professor Dr. Markus Morgenstern; Professor Dr. Achim Rosch; Professor Dr. Simon Stellmer; Professor Dr. Martin Weitz