The researches are supported by the 973 program, the national National Key Research and Development Program, the National Natural Science Foundation, the State Key Laboratory of Precision Measurement Technology and Instruments, and etc.
(1) Microwave frequency standard based on laser cooled Cadmium ions
The microwave frequency standard based on laser cooled cadmium ions has promising performance of frequency stability and accuracy, and it can be transportable due to relative low complexity. The main researches include the techniques of laser cooling, sympathetic cooling, improvement of short-term frequency stability and uncertainty, integration technique, and etc.
(2)Ramsey-CPT microwave frequency standards
The Ramsey-CPT microwave frequency standard is a kind of improved coherent population trapping (CPT) clocks with the separated oscillation fields technique and detection based on orthogonal polarization. The main researches include the detection based on orthogonal polarization, time sequence control with FPGA, and interleaving lock.
(3) Laser frequency stabilization and precision spectroscopy
The precision spectroscopy based on the frequency stabilized lasers offers us the ultra-high measurement resolution, which can be widely applied in gas detection, metrology, and industrial precision detection. The main researches include ultra-narrow linewidth laser, frequency stabilization based on atomic or molecular lines, and the related applications.