Enhanced Loading of 40K from Natural Abundance Potassium Source with a High Performance 2D+ MOT**Supported by the National Key Research and Development Program of China under Grant Nos 2016YFA0300600 and 2016YFA0301500, and the National Natural Science Foundation of China under Grant Nos 11474347, 61227902 and 61775232.

Abstract

40K is one of the most important atomic species for ultra-cold atomic physics. Due to the extremely low concentration (0.012%) of 40K in natural abundance of potassium, most experiments use 4–10% enriched potassium source, which have greatly suffered from the extremely low annual production and significant price hikes in recent years. Using naturally abundant potassium source, we capture 5.4×106 cold 40K atoms with the help of a high performance of two-dimensional magneto-optical trap (2D+ MOT), which is almost three orders of magnitude greater than previous results without the 2D+ MOT. The number of the 40K atoms is sufficient for most ultra-cold 40K experiments, and our approach provides an ideal alternative for the field.