Miniaturized microwave cavity for Rubidium atomic frequency standards

In view of mobile and battery-powered applications, there is an increasing demand for more radically miniaturized and low-power atomic frequency standards. For the miniaturization of a double-resonance Rubidium atomic clocks, the size reduction of the microwave cavity or microwave resonator (MWR) to well below the wavelength of the atomic transition (6.835 GHz in the case of ⁸⁷Rb) has been a longstanding issue. In this paper we propose a new miniaturized MWR, the μ-LGR, that meets the requirements for the atomic clock application while the structure is very compact, and assembly can be performed using standard and potentially low-cost techniques. Concept of the proposed device was proven through simulation and prototypes were successfully tested, showing the μ-LGR to be suitable for the integration in a miniaturized atomic clock.