Development of the integrated integrating sphere cold atom clock

We develop an integrated integrating sphere cold atom clock (ISCAC), which mainly consists of physical package, laser system, microwave source, and electronics. This compact system is more stable and reliable than the previous version. The experimental results show that the short term frequency stability of 5.4×10^-13τ^-1/2 and 2.9×10^-15 at 1-day integrating time are achieved.