Progress report on the improved linear ion trap physics package

This article describes the first operational results from the extended linear ion trap frequency standard now being developed at JPL. This new design separates the state selection/interrogation region from the more critical microwave resonance region where the multiplied local oscillator (LO) signal is compared to the stable atomic transition. Hg ⁺ ions have been trapped, shuttled back and forth between the resonance and state selection traps. In addition, microwave transitions between the Hg⁺ clock levels have been driven in the resonance trap and detected in the state selection trap