Multi-frequency telecom fibered laser system for potassium laser cooling

Charbel Cherfan (1) , Maxime Denis (1) , Denis Bacquet (1) , Michel Gamot (1) , Samir Zemmouri (1) , Isam Manai (1) , Jean-François Clément (1) , Jean-Claude Garreau (2) , Pascal Szriftgiser (1) , Radu Chicireanu (1)

1 PhLAM - Laboratoire de Physique des Lasers, Atomes et Molécules - UMR 8523
2 Atomes Froids - Atomes Froids

We describe a compact and versatile multi-frequency laser system for laser-cooling potassium atoms, by frequency doubling a fiber-optic telecom beam ($\simeq 1534$ or $1540$~nm). Low-power fiber-based telecom lasers and components generate a single beam containing the cooling and repumper half frequencies, subsequently amplified by high-power amplifier. A final free-space SHG stage generates a single beam with typically 2.5 W at quasi-resonant frequencies ($\simeq 767$ or $770$~nm) with high-quality mode and ready for laser cooling. This allowed to trap up to $4\times10^9$ $^{41}$K atoms with fast loading times (2.5 s) at sub-Doppler temperatures of 16~$\mu$K. This opens promising perspectives towards versatile and transportable ultracold atom setups.

Domaines: Optique [physics.optics]; Dynamique Chaotique [nlin.CD]; Physique Quantique [quant-ph]

Charbel Cherfan, Maxime Denis, Denis Bacquet, Michel Gamot, Samir Zemmouri, et al.. Multi-frequency telecom fibered laser system for potassium laser cooling. Applied Physics Letters, 2021, 119 (20), pp.204001. ⟨10.1063/5.0070646⟩. ⟨hal-03358006⟩