Achromatic, planar Fresnel-reflector for a single-beam magneto-optical trap

Area of Science:

• Atomic, Molecular, and Optical Physics
• Quantum Optics
• Laser Cooling and Trapping

Background:

• Planar structures based on diffraction gratings have dominated single-beam atom trapping.
• These grating-based structures suffer from chromaticity, leading to complex designs and fabrication challenges.
• Chromaticity in gratings causes wavelength-dependent axial displacements, limiting trap performance.

Purpose of the Study:

• To introduce a novel achromatic, planar, periodic mirror structure for single-beam magneto-optical trapping (MOT).
• To demonstrate the utility of this Fresnel-inspired structure for strontium isotope cooling and trapping.
• To overcome the limitations of existing diffraction grating-based planar structures.

Main Methods:

• Design and fabrication of a Fresnel-reflector structure inspired by Fresnel lenses.
• Utilizing the structure for first- and second-stage cooling and trapping of strontium isotopes.
• Characterizing the achromatic beam steering and planar architecture advantages.

Main Results:

• The Fresnel magneto-optical trap (MOT) structure is achromatic and planar.
• It successfully enabled cooling and trapping of different strontium isotopes.
• The structure avoids chromaticity issues inherent in diffraction gratings.
• It allows for miniaturization and multi-species trapping in a single volume.

Conclusions:

• The Fresnel-reflector structure offers a versatile and easy-to-manufacture alternative for single-beam MOTs.
• This technology enables miniaturized cold-atom systems for alkaline-earth-like atoms.
• It facilitates widespread adoption of advanced cold-atom experiments and applications.