Acetylene-based frequency stabilization of a laser system for potassium laser cooling

We demonstrate a laser frequency stabilization technique for laser cooling of potassium atoms, based on saturated absorption spectroscopy in the C-Band optical telecommunication window, using ro-vibrational transitions of the acetylene molecule ( C H ). We identified and characterized several molecular lines, which allow to address each of the potassium D2 (767 nm) and D1 (770 nm) cooling transitions, thanks to a high-power second harmonic generation (SHG) stage. We successfully used this laser system to cool the K isotope of potassium in a 2D-3D Magneto-Optical Traps setup.