Portable Optical Atomic Clock Based on a Dichroic Two-Photon Transition in Rubidium

We report progress on development of a next generation timing reference based on an optical transition in rubidium coupled with a compact optical frequency comb to deliver a high stability RF reference signal. Engineering models that indicate the entire system including all optical components and control electronics could occupy a volume of 25 L, have a weight of 17 kg and consume 100 W of power. Such a device would be useful in GPS denied or contested environments.