A Lamp-Pumped Rubidium Atomic Frequency Standard with a Short-Term Stability at the Level of 2 × 10 −13 τ −1/2

Abstract

A high-performance lamp-pumped rubidium atomic frequency standard (RAFS) prototype is developed. In the physics package of the RAFS, a rubidium spectral lamp with Xe as the starting gas and the isotope filtering technique are used to depress the optical shot noise of atomic signal. 30 mm-diameter absorption and filter cells located in a slotted-tube microwave cavity are utilized to increase the amplitude of clock transition signal. For the electronic system, a new low phase noise microwave chain is developed. The frequency stability measurement of the prototype shows a short-term frequency stability of 2.1 × 10−13τ−1/2 within 1 s–100 s. This is the best short-term stability result for rubidium clock obtained so far, suggesting that the stability of the traditional RAFS could be comparable to that of the laser-pumped RAFS.