In August 2020, the spokespersons of the Excellence Cluster MCQST – Immanuel Bloch, Ignacio Cirac and Rudolf Gross – started an initiative to establish the Munich Quantum Valley. In a strategy paper, written with support of Max-Planck Vice President Klaus Blaum and FhG Research Director Raoul Klingner, they pointed out that the larger Munich area with its excellent research institutions as well as its active industrial, high-tech and venture capital environment is ideally suited to establish a unique European center for quantum science and technology (QST).

Financial support of MQV was immediately included into the Bavarian «Hightech Agenda Plus». Meanwhile, a Memorandum of Understanding has been signed by Prime Minister Söder and the presidents of the five founding research organizations (see MQV Kick-off event). For 2022/23, a budget of 120 Mio. €  is already allocated and a total budget of 300 Mio. € is planned. By MQV, Bavaria as a whole will be developed into a leading international center with the potential to attract the best researchers and open up new opportunities for Bavaria as a business location in this innovative field. To implement MQV, the following three-point plan was proposed in the strategy paper will be implemented:

1. Foundation of a Center for Quantum Computing and Quantum Technology to foster networking with industry, to develop priorities in QST R&D, and to coordinate the allocation of funding with the following priorities:
   • Development, realization and operation of quantum computers based on a longterm institutional funding to guarantee international competitiveness.
   • Support of basic science and development of basic quantum technologies within so-called lighthouse projects.
   • Technology transfer to industry and start-ups.
2. Establishment of a Quantum Technology Park to provide the technological infrastructure for the development and fabrication of quantum devices.
3. Qualification and Education of the next generation of quantum experts in natural and computer sciences as well as engineering, including training and re-education of skilled employees in industry.

Quantum Mechanics and Information Science have revolutionized our modern world beyond imagination. Whilst quantum mechanics forms the basis for our understanding of the microscopic world, information science is the basic building block for information processing and communication in our digital age. Today we are witnessing a scientific and technological revolution in which Information Science and Quantum Mechanics no longer stand as separate entities, but have rather been united in the common language of Quantum Information Science. First developed to describe the working principles of future Quantum Computers, Quantum Information Science has emerged as an even more powerful description of our physical world, with wide ranging relevance, directly linking fields such as quantum materials and quantum chemistry to seemingly disparate fields such as the cosmology of black holes. At the core of this description is the notion of entanglement, an essential feature without any classical analogue that is responsible for a plethora of astonishing phenomena and applications of Quantum Physics.

These dramatic developments have led to the new combined research field of Quantum Science and Technology (QST), in which these diverse topics, their interconnection as well as their consequences for practical applications are being explored. QST unites multidisciplinary research across physics, mathematics, computer science, electrical engineering, materials science, chemistry, and recently, even cosmology and high energy physics.The core goal of the Munich Center for Quantum Science and Technology (MCQST) is to discover and understand the novel and unifying concepts in the interdisciplinary research fields of QST and to make them tangible and practical, to develop the extraordinary applications within reach by building next-generation quantum devices.

At a fundamental science level, this includes the comprehensive understanding and control of entanglement in quantum many-body systems spanning different time, length and energy scales, through novel theoretical and experimental approaches in quantum information science. Applications for Quantum Devices and Materials to be developed at MCQST range from inherently secure communication and processing of information to ultrasensitive sensors and transducers for precision metrology.Munich is in a unique position to form such a world-leading research center in QST due to its longstanding experience, broad and proven interdisciplinary expertise, and outstanding excellence of the participating senior and junior researchers in all core fields of QST. Developing education and support for junior researchers in QST as well as advancing the strengths of Munich research structures within MCQST will ensure long-term and high-impact research as well as an ideal entry point for industry in this increasingly important field. It will allow Munich to achieve an outstanding visibility and assume a leading position in QST research.

The International Max Planck Research School for Quantum Science and Technology is a joint program of the Max Planck Institute of Quantum Optics, the Ludwig-Maximilians-Universität München and the Technical University of Munich. It offers an excellent and coherent graduate program across the fields of atomic physics, quantum optics, solid state physics, material science, quantum information theory, and quantum many-body systems.

First and foremost, IMPRS-QST provides a platform of joint activities for a large research community, encouraging better networking and scientific exchange as an integral part of doctoral training.

IMPRS-QST students can either get directly admitted to the program through our yearly application process or join as members after starting their PhD at one of our associated research groups. 

In the greater Munich area there is an extremely active cluster of institutions and research centers committed to the highest standards of excellence in research and teaching in the field of quantum science and technology.

The members and principal investigators of the Munich Quantum Center (MQC) research groups meet up regularly at common workshops and seminars to create a very interactive ambience for quantum science in Munich. The MQC was born at the heart of this vivid atmosphere, gathering over 50 research groups belonging to four different institutions: the Ludwig-Maximilians-Universität München, the Technical University of Munich, the Max Planck Institute of Quantum Optics, and the Walther-Meißner-Institute for Low Temperature Research.

Our research covers a wide array of topics ranging from mathematical foundations, quantum information, computational methods, quantum nano-systems, quantum optics, and quantum many-body physics to superconducting quantum devices.

This quantum algorithm determines the groundstate of a given Hamiltonian, for example a molecular electronic configuration Hamiltonian. The quantum state of the system is steered to the target state by varying parameters of a gate sequence on the qubits to optimize a cost function on a classical computer. The advantage of such a hybrid quantum-classical computation over a purely classical one is that high-dimensional multi-qubit states can be stored efficiently on the quantum device, which is not possible on a classical memory because of the exponentially large number of state coefficients. The challenge on today’s quantum computers is, however, that the VQE algorithm has to converge to the target state before decoherence sets in. It's circuit-depth must be short. The main aim of this project is, therefore, to explore the efficient generation of multi-qubit states going beyond the current paradigm of decomposing all state manipulations into single and two-qubit gates. We will investigate multi-qubit operations that will allow us to entangle multiple qubits at the same time. This will result in short-depth efficient algorithms provided that the fidelity of the multi-qubit gate can be kept high. We use fixed-frequency transmon qubits and two-qubit gates based on parametrically driven tunable couplers. We address the question if there is an advantage in using multi-qubit gates over traditional two-qubit gates not only in theory but also in practical experiments. While theoretically the answer is likely to be affirmative, on the experimental side it is not clear what gate fidelities can be reached and how these compare to a decomposition of multi-qubit gates into two-qubit interactions. We explore N-way tunable couplers that are either capacitively and galvanically coupled to N qubits and evaluate the maximum number of qubits. We investigate multi-qubit entangling interactions via parametric frequency-modulation of the coupler. Different methods are compared, such as resonant or dispersive interactions based on simultaneous pulses to generate different classes of entangled states. The final goal is a four-qubit experiment targeting a quantum chemistry problem, such as determining the ground state and energy spectrum of molecular hydrogen (H2), and to assess the efficiency of multi-qubit gates. It is straightforward to then extend the methods that are tested in this project with a few qubits to larger systems to bring practical applications closer within reach by adding building blocks with higher connectivity and multi-qubit gate capabilities.

Within this project, we join experts from experimental and theoretical physics and materials science to tackle these problems. We will employ kappa-type organic charge transfer salts as quasi-2D electronic model systems with bandwidth-controlled Mott instability for tracking the evolution of key characteristics of the charge carriers in the metal/insulator coexistence region of the phase diagram as well as in the neighboring homogeneous metallic state. In particular, we will study (i) the correlation-induced renormalization of the effective mass, (ii) the exact geometry and topology of the Fermi surface, and (iii) the coherence of charge transport. The systematic study of these characteristics in well-defined model systems will provide a crucial test for the existing theories of the Mott metal-insulator transition.A key objective of the project is the disentanglement of contributions of charge, spin, and lattice degrees of freedom to the metal-insulator instability. This problem will be addressed by studying kappa-type salts with different strength of geometrical frustration, magnetic interactions, and lattice disorder. The salts of BEDT-TTF with different anions are particularly suited for studying the effects of geometrical frustration, while BETS salts with localized magnetic moments give access to the interplay between electronic correlations and magnetic interactions. The coupling of the electronic state to lattice degrees of freedom will be probed by studying the influence of deuteration of BEDT-TTF salts on the charge carrier properties and by tracing the impact of ethylene-group disorder in these salts.The main experimental probes for addressing the above issues will be magnetic quantum oscillations, semiclassical anisotropic magnetotransport, and resistivity anisotropy. A precise control of the electronic ground state with respect to the metal-insulator boundary will be realized by fine-tuning materials with quasi-hydrostatic pressure as well as "chemical pressure". A quantitative analysis of the experimental results will be carried out by the theory team involved in the project using the state-of-the-art theory of high-field magnetotransport in quasi-2D metals as well as of the charge transport in phase-separated electronic media. Further development of the (magneto)transport theory in the segments related to the proposed experiments is planned.The availability of top-quality single crystals of kappa-type salts is crucial for the success of the planned project. The preparation and characterization of such crystals will be carried out by the experienced materials science team of the project.