A transportable frequency comb for precision measurements with optical clocks outside of laboratories and for precision spectroscopy of ions and molecules

• Subject Area: Optics, Quantum Optics and Physics of Atoms, Molecules and Plasmas
• Term: Funded in 2019
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 420774082

The central device of this proposal in a transportable frequency comb. This frequency comb will allow for measurement campaigns in the field and will also increase the measurement resolution for measurements in the lab.The main application of this frequency comb is measurements with a transportable Strontium based optical atomic clock in the field. The transportability of the clock has already been demonstrated. In order to increase the accuracy of the clock, a new lattice laser is also applied for. The project aims for precision measurements of the time dilation in the gravitational field of the earth at different places. Using the microwave terminal on the international space station, the transportable clock shall be compared with clocks in Europe while it is operated in South America. These measurements aim to improve the quality of geodetic data about this continent.In the course of another project, the requested frequency comb will be used to characterize a special transportable Ytterbium-clock during its development. This clock will allow measurements of the gravitational field from a stratospheric balloon. Once the development of the clock is finished, the frequency comb will serve to aid comparison of the clock in the balloon with the clock on the ground.Other planned applications of the frequency comb are precision spectroscopy on cold molecular hydrogen ions, characterization of ultra-stable optical resonators as well as research on spectral holes in Europium-doped crystals.

• DFG Programme: Major Research Instrumentation
• Major Instrumentation: Transportabler Frequenzkamm
• Instrumentation Group: 5780 Nichtlineare Optik (Frequenzvervielfacher)
• Applicant Institution: Heinrich-Heine-Universität Düsseldorf
• Leader: Professor Stephan Schiller, Ph.D.