Abstract
In this work, we have designed a new version of power amplifier and beam shaping which have been employed successfully for cooling and repumping light after second tapered amplifier for better coupling efficiency of both potassium and rubidium simultaneously. We have also constructed the setup of absorption image technique for more accurate measurements. In this experiment, $2.3\times10^{8}$ of cold potassium atoms were produced in the MOT, and about 10\,\% of them were loaded into the magnetic trap. The subsequent magnetic transferring to the science cell was achieved with a linear moving track and an efficiency of 24\,\%. After transferring to science cell, the lifetime increased to 32.44 s due to the reduced background collision. Meanwhile, we also trapped and transferred $^{39}\rm{K}$ and $^{87}\rm{Rb}$ simultaneously to the science cell. The number is $3.1\times10^{6}$ with a temperature 160 $\mu$K for potassium and $1.8\times10^{7}$ with a temperature 133 $\mu$K for rubidium, respectively. Because of the additional loss caused by the inter-species collision, the lifetime of $^{39}\rm{K}$ was reduced to 27.06 s.