arXiv subjects

Saskia Bondza

Publications and source records attributed to Saskia Bondza.

3 recordsLinked to original sources

arXiv2026

Miniaturized vacuum package for magneto-optical trapping of strontium

Quantum sensors, like optical lattice clocks, undergo a continuous development from lab-based towards mobile systems. A key aspect in the miniaturization of the experimental setups is the development of compact atom sources. Conventional atom sources for alkaline-earth-like elements consist of a high-power oven and a six-beam magneto-optical trap (MOT) inside of vacuum chamber with extensive flanges, viewports and electrical feedthroughs. Here we present a highly compact vacuum package utilizing key technologies for future quantum sensor systems: A chip-based low-power atomic oven, a planar grating MOT chip, and a miniaturized vacuum pump all held inside an additively manufactured titanium vacuum chamber, featuring custom-sized vacuum flanges. In this miniaturized setup, spanning a volume of only 750 ml, we trap up to $10^5$ Sr atoms in a MOT, requiring an oven heating power below 1 W.

physics.atom-ph↗

arXiv2023

Achromatic, planar Fresnel-Reflector for a Single-beam Magneto-optical Trap

We present a novel achromatic, planar, periodic mirror structure for single-beam magneto-optical trapping and demonstrate its use in first- and second-stage cooling and trapping for different isotopes of strontium. We refer to it as Fresnel MOT as the structure is inspired by Fresnel lenses. By design, it avoids many of the problems that arise for multi-color cooling using planar structures based on diffraction gratings, which have been the dominant planar structures to be used for single-beam trapping thus far. In addition to a complex design process and cost-intensive fabrication, diffraction gratings suffer from their inherent chromaticity, which causes different axial displacements of trap volumes for the different wavelengths and necessitates tradeoffs in their diffraction properties and achievable trap depths. In contrast, the Fresnel reflector structure presented here is a versatile, easy-to-manufacture device that combines achromatic beam steering with the advantages of a planar architecture. It enables miniaturizing trapping systems for alkaline-earth-like atoms with multiple cooling transitions as well as multi-species trapping in the ideal tetrahedral configuration and within the same volume above the structure. Our design presents a novel approach for the miniaturization of cold-atom systems based on single-beam MOTs and enables the widespread adoption of these systems.

physics.atom-ph↗

arXiv2021

Two-color grating magneto-optical trap for narrow-line laser cooling

We demonstrate for the first time the two-color cooling and trapping of alkaline-earth atoms in a grating magneto-optical trap (gMOT). The trap is formed by a single incident laser beam together with four secondary beams that are generated via diffraction from a nanostructured wafer. A grating structure for a gMOT operating with strontium atoms is optimized and fabricated. We trap $10^6$ $^{88}$Sr atoms on the $^1$S$_0$ $\rightarrow$ $^1$P$_1$ transition at $461\;\mathrm{nm}$ and transfer $25\;\%$ of these atoms to the second cooling stage on the narrower $^1$S$_0$ $\rightarrow$ $^3$P$_1$ intercombination transition at $689\;\mathrm{nm}$, preparing a sample of $2.5\times 10^5$ atoms at $5\;μ$K. These results demonstrate for the first time the applicability of the gMOT technology in conjunction with two widely differing wavelengths and enable the continued miniaturization of alkaline-earth based quantum technologies like optical atomic clocks.

physics.atom-ph↗