Manipulating and measuring single atoms in the Maltese cross geometry

Area of Science:

• Atomic, Molecular, and Optical Physics
• Quantum Technologies
• Nanophotonics

Background:

• High numerical aperture (high-NA) optical microtraps are crucial for manipulating neutral atoms in quantum technology.
• The novel Maltese cross geometry (MCG) atom trap utilizes four in-vacuum lenses for multi-directional high-NA optical coupling.
• This work provides the first comprehensive characterization of atomic behavior within an MCG atom trap.

Purpose of the Study:

• To extensively characterize the performance and atomic behavior in a newly developed Maltese cross geometry (MCG) atom trap.
• To evaluate the MCG trap's efficiency, loading rate, atomic lifetime, temperature, and fluorescence properties.
• To develop and demonstrate a new method for mapping collection efficiency using the trap's multi-directional access.

Main Methods:

• Utilized an optimized MCG system for high coupling efficiency measurements.
• Measured key trap parameters including occupancy, loading rate, lifetime, temperature, and trap frequencies.
• Developed a novel technique using four-directional access to map the spatial distribution of collection efficiency from high-NA optics by correlating fluorescence signals.

Main Results:

• Observed trap characteristics comparable to existing single-atom traps with fewer optical access points.
• Demonstrated that the measured collection efficiency distribution aligns with theoretical predictions from Gaussian beam optics.
• Successfully mapped the spatial distribution of single-mode collection efficiency.

Conclusions:

• The Maltese cross geometry provides essential multi-directional high-NA access for advanced atomic manipulation and measurement.
• MCG traps maintain critical characteristics like lifetime, temperature, and trap size.
• This geometry significantly enhances capabilities for quantum technology applications compared to systems with limited access directions.