Integrated fiber-mirror ion trap for strong ion-cavity coupling

Area of Science:

• Quantum Optics
• Atomic Physics
• Experimental Physics

Background:

• Cavity quantum electrodynamics (Cavity-QED) experiments with trapped ions require precise integration of optical cavities and ion traps.
• Existing methods face challenges in miniaturization and minimizing optical element influence on ion trapping potentials.

Purpose of the Study:

• To present and characterize fiber mirrors and a miniaturized ion trap for integrating fiber-based Fabry-Perot cavities (FFPCs) with linear Paul traps.
• To enable cavity-QED experiments with trapped ions using novel, integrated optical components.

Main Methods:

• Fabrication of fiber mirrors and a miniaturized linear Paul trap.
• Characterization using optical profilometry, finesse measurements, and X-ray photoelectron spectroscopy.
• Numerical calculation of trap potentials and experimental compensation strategies.

Main Results:

• Successful integration of FFPCs with small mode volumes into a miniaturized Paul trap, minimizing mirror influence on ion pseudopotential.
• Achieved single-atom cooperativity up to 12 for FFPCs longer than 200 μm, with scattering losses comparable to substrate mirrors.
• Demonstrated FFPCs with degenerate polarization modes and developed procedures for handling, alignment, and cleaning.

Conclusions:

• The developed fiber mirrors and miniaturized ion trap design are suitable for cavity-QED experiments with trapped ions.
• This novel integration offers a pathway to enhanced performance and scalability in trapped-ion quantum systems.
• Further research into annealing processes and mirror coating optimization can further reduce losses.