The Research of Miniaturization CPT Rb Atomic Clocks

Abstract

Based on current situation of the study in this area, our work will introduce a miniature CPT atomic clock system with small physical size, high stability and lower power consumption. The use of our original innovational technology to fabricate small cells can avoid the complexity and difficulty of the anodic bonding technology. By this technology, we could accomplish the objective to minimize the occupied volume of the physical part of the system to 1 cm³. The single FPGA chip is the main part of the control circuit to accomplish the slower start-up of the laser, two necessary locking loops to make the system work, and the temperature control logic. Our 3.035 GHz RF signal is generated from a TCXO via the technology of DDS. Our prototype is a significant progress to realize CSAC with the use of the single FPGA chip. We demonstrate our CPT clock prototype with the volume less than 100 cm³. This prototype has frequency instability of $1 \times 10^{ - 10}$ for 1 s and $3 \times 10^{ - 11}$ for 1000 s.