Most recent result of pulsed microwave hydrogen maser

Adequate coherent pulsed microwave input into microwave cavity of atomic clock can induce Ramsey fringes of the atomic transition, by which the line width of atomic clock can be greatly reduced and the performance might be improved. This method has been applied to the pulsed optically pumped (POP) rubidium clock. Shanghai Astronomical Observatory has studied the application of this method in passive hydrogen maser. Electrical circuit for pulsed microwave frequency sweeping has been designed, and the Ramsey fringes of hydrogen atom have been observed, which means that this method for passive hydrogen maser is feasible. We plan to optimize the parameters of the system and microwave pulse to further reduce the line width and design full-scale servo circuit to realize the pulsed microwave hydrogen maser. Finally system performance will be measured and optimized. This work is original in China.