Nicola Poccia's group synthesizes topological superconductors in complex quantum matter. We focus on artificial systems that are free from lattice matching constraints and where the collective properties in a wide range of temperatures and external fields are controlled by a multi-component and space-time organization. After synthesis, we explore the electronic and structural properties by means of a variety of experimental probes, including electronic transport at the nanoscale and synchrotron radiation microscopies resolved in space and time. Our main focus is to advance the tools for the synthesis, nanoscale imaging and control of topological superconductors in complex quantum matter. Our ultimate challenge is to realize specifically tailored topological superconducting properties in complex quantum matter that are robust up to room temperature. Although we are driven by curiosity, we keep an eye open for applications of our research in solid state quantum technologies that need higher operation temperatures.
Head of Research Group "Superconducting Nanodevices"
Room: A 3E.06.2
Phone: +49 351 4659 527
We have developed a bismuth-based, two-dimensional superconductor that is only one nanometer thick. By studying fluctuations in this ultra-thin material as it transitions into superconductivity, we can gain insight into the processes that drive superconductivity more generally.
We have realized a system containing 90,000 superconducting niobium nano-sized islands on top of a gold film. In this configuration, the vortices find it energetically easiest to settle into energy dimples in an arrangement like an egg crate — and make the material act as a Mott insulator, since the vortices won’t move if the applied electric current is small. When they applied a large enough electric current, we observed a dynamic Mott transition as the system flipped to become a conducting metal; the properties of the material had changed as the current pushed it out of equilibrium.
We used advanced X-ray microscopies to study the fractal spatial correlation of quantum matter in superconductors, favouring quantum coherent-states at high temperature.
Proceedings of the National Academy of Sciences 109.39 (2012): 15685-15690.
We have realized set-up to write/erase and monitor robust superconducting regions in a disordered matrix of a high temperature superconductors. The technique can be used to spatially organize the ordering of defects in superconductors and control its mesoscale properties. The X-ray beam is focused on the sample and then a charge-coupled device (CCD) camera is used to detect the X-ray reflection.