Research group | Quantum Sensors with Cold Ions
The research group “Quantum Sensors with Cold Ions” investigates the potential of ultra-stable optical clocks for applications in navigation and the measurement of gravity potentials. Innovative ion-trap chips with integrated electronic circuits are being developed to scale up the number of ions in micro-structured and segmented traps. In arrays of up to 100 trapped and laser cooled ions, atomic frequencies are measured with a fractional resolution of up to 10-18 within a significantly reduced integration time.
This allows the measurement of geodetic heights above the geoid with a resolution of one centimetre due to the relativistic redshift. For the ultra-precise trap structures, laser structuring and sputtering techniques are being developed with μm tolerances and nm surface roughness. In these chip traps, coulomb crystals of indium and ytterbium ions are cooled and investigated with high-resolution spectroscopy at temperatures below 1 mK.