The research of the QEC group focusses on the quantum engineering of building blocks and devices which are essential for all areas of photonic quantum technologies. These building blocks are sources of non-classical light such as single-photons or entangled photons, spin-photon interfaces, quantum memories and single photon detectors. Overall, the group’s research spans the entire range from engineering light-matter interactions to demonstrator experiments, which enable systems engineering, and can be divided into three interlinked areas:
Research area A addresses the investigation of novel optically-active quantum materials and the development of novel quantum-optical techniques. Specific properties that are investigated are quantum-optical and spin coherence properties. Since every quantum material has specific advantages and disadvantageous and future systems are likely to be hybrid quantum systems the group works with a variety of materials, including semiconductor quantum dots, color centers in diamond, rare-earth ions in crystals, atomically-thin transition metal dichalcogenides and superconducting nanowires. Quantum-optical techniques that the group develops are techniques for the coherent-optical control of electronic excitations and spin states, as well as techniques for the generation and detection of non-classical light.
Research area B addresses the engineering of modular building blocks and quantum photonic-integrated circuits for photonic quantum technologies. Embedding optically-active quantum systems into nanophotonic resonators allows to enhance the light matter interaction thus increasing operational rates. Moreover, tailored nanophotonic resonators allow for efficient photonic interfacing. In addition to working with many different quantum materials, the QEC group works also on a large number of different nanophotonic structures to use for each application the best suitable nanophotonic resonator. In addition, different building blocks can be integrated on a chip to form scalable quantum photonic-integrated circuits.
Research area C addresses the realization of demonstrator experiments to obtain feedback for the device engineering and to enable systems engineering. Here, the techniques developed in area A and the devices engineered in area B are combined to realize demonstrator experiments such as quantum communication or photonic quantum computing. Results from these experiments give feedback for the device engineering, i.e. which parameters turn out to be particularly important in real-world settings. In addition, the demonstrator experiments enable systems engineering and allow to develop protocols for photonic quantum technologies.