Atom camera: super-resolution scanning microscope of a light pattern with a single ultracold atom.

Area of Science:

• Atomic, Molecular, and Optical (AMO) Physics
• Biophysics
• Quantum Imaging

Background:

• Sub-micrometer light patterns are crucial in various scientific fields.
• Current in situ characterization methods lack sufficient spatial resolution and sensitivity.

Purpose of the Study:

• To develop a novel high-resolution, high-sensitivity imaging technique for sub-micrometer light patterns.
• To overcome the limitations of existing imaging methods, particularly those related to diffraction and thermal fluctuations.

Main Methods:

• Utilizing a single ultracold atom trapped in an optical tweezer as a scanning probe.
• Measuring energy shifts in atom spin states using polarization-sensitive transitions.
• Achieving quantum-limited spatial resolution by suppressing position uncertainty to near quantum fluctuations.

Main Results:

• Demonstrated 2D imaging of both light intensity and polarization ellipticity with high resolution.
• Characterized the non-trivial polarization profile of a tightly-focused beam.
• Achieved a spatial resolution upper bound of σ ≤ 96(4) nm, surpassing previous methods.

Conclusions:

• The atom camera provides a powerful new tool for analyzing sub-micrometer light patterns.
• This technique enables imaging beyond the diffraction limit, advancing optical physics and biophysics.
• The method offers superior sensitivity and resolution compared to existing approaches.