Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

A: Fachverband Atomphysik

A 26: Poster – Ultracold Matter (joint session Q/A)

A 26.23: Poster

Mittwoch, 4. März 2026, 17:00–19:00, Philo 2. OG

Individual cooler and repumper power stabilisation for counting 6Li-atoms — •Armin Mirzaei Kian, Johannes Reiter, Paul Hill, Maciej Galka, and Selim Jochim — Physikalisches Institut, Universität Heidelberg, Deutschland

Precise counting of the number of atoms in a magneto-optical trap down to the single atom level relies on the high-fidelity discrimination between atoms based on their total fluorescence intensity. Experimentally, the latter is altered by laser power fluctuations. In this work we present a technique to improve the signal to noise ratio of counting 6Li-atoms by frequency modulation of the cooler and repumper beams. This method is chosen since the combined beam is indinstinguishable in its properties like polarisation and mode except the small frequency difference resulting in a beat note. Modulating the Acousto-Optic-Modulators of both cooler and repumper by two frequencies respectively, additional sidebands are generated whose amplitudes are proportional to the optical powers of the beams. With subsequent demodulation these signals can be used to feedback and stabilise cooler and repumper power individually, leading to a stronger discrimination of atom number.

Keywords: Heterodyne Beats; Counting Lithium-6 atoms; Power stabilisation; Frequency modulation