Design of mercury lamp for trapped ion frequency standards

The mercury ion trapped microwave frequency standard has the potential applications for the future satellite, deep space explorations, time keeping and broadcasting for its great advantages in the total volume, stability and lifetime. The high frequency spectrum of mercury ion trapped microwave frequency standard is pumped by the mercury lamp which has small volume and long lifetime, as the base of superiority of mercury ion trapped microwave frequency standard. However, the mercury RF discharge lamp used for optical pumping and state detection may limit the ultimate stability performance of the clock. So we have carried out many experiments to enhance the light stability and the ratio of useful light at 194nm and unwanted background light at 254nm (194/254). Finally, the stability of light power is about 3% in 3 days, the 194/254 ratio is about 1/45, and with filter bulb the ratio is about 1/3. The experimental system of mercury ion trapped microwave frequency standard will be introduced and the Hg lamp device is presented with the radiation regime.