Multi-frequency telecom fibered laser system for potassium laser cooling

Abstract

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 $4\times 10^9$ ${}^{41}$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.

References in corpus (3)

• All optical cooling of ${}^{39}$K to Bose Einstein condensation
• Production of large ${}^{41}$K Bose-Einstein condensates using D1 gray molasses
• Direct evaporative cooling of 41K into a Bose-Einstein condensate