Setup and preliminary characterization of a surface-electrode Paul trap for frequency metrology

This thesis presents advancements in the development of a transportable ytterbium single-ion optical clock, focusing on the integration of a microfabricated surface electrode trap into the experimental setup. The research explores the optimization of ion trapping systems to enhance stability, targeting applications in precision metrology, fundamental physics, and geodesy.

The work addresses the theoretical principles of ion trapping, highlighting the challenges posed by micromotion, motional heating, and quantum projection noise, as well as the strategies for overcoming these limitations. It also investigates the detection processes and the interplay between trap design and clock performance. A comprehensive approach combines theoretical modeling, electrical testing, and experimental measurements to refine the trap’s design and operation. The experimental setup integrates stabilized lasers, optimized RF and DC voltage controls, and ultra-high vacuum systems to trap and interrogate ¹⁷¹Yb⁺ ions effectively.

Notable achievements include the stabilization of laser frequencies to a hollow cathode Yb lamp, achieving fractional frequency stability below 10⁻⁹, and the design of a high-quality RF resonator with significantly improved performance. Enhanced vacuum levels and a new dispenser design led to more efficient ion loading and extended trap lifetimes. The study also highlights challenges encountered in the trap’s operation, including unexpected voltage breakdown behaviors, and suggests future improvements in chip design and microfabrication processes. These findings offer valuable insights into the limitations and potential of microfabricated surface traps in optical clock applications.

In conclusion, this research advances the understanding and implementation of surface ion traps, contributing to the development of compact and transportable optical atomic clocks. The results provide a strong foundation for further innovation, addressing existing challenges while paving the way for new applications in precision timekeeping and related fields.

spectroscopy, time and frequency metrology, single-ion trapping, laser cooling, atomic clock.

Full document (EN) : TEL-05603323