Compact Microwave Mercury Ion Clock for Space Applications

Prestage, John D.; Tu, Meirong; Chung, Sang K.; MacNeal, Paul

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NASA NTRS · 20090034988

Compact Microwave Mercury Ion Clock for Space Applications

Prestage, John D.·Tu, Meirong·Chung, Sang K.·MacNeal, Paul

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Abstract

We review progress in developing a small Hg ion clock for space operation based on breadboard ion-clock physics package where Hg ions are shuttled between a quadrupole and a 16-pole rf trap. With this architecture we have demonstrated short-term stability approx.1-2x10(exp -13) at 1 second, averaging to 10-15 at 1 day. This development shows that H-maser quality stabilities can be produced in a small clock package, comparable in size to an ultra-stable quartz oscillator required or holding 1-2x10(exp -13) at 1 second. We have completed an ion clock physics package designed to withstand vibration of launch and are currently building a approx. 1 kg engineering model for test. We also discuss frequency steering software algorithms that simultaneously measure ion signal size and lamp light output, useful for long term operation and self-optimization of microwave power and return engineering data.

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Prestage, John D., Tu, Meirong, Chung, Sang K., MacNeal, Paul. 2007-11-27. Compact Microwave Mercury Ion Clock for Space Applications. https://ntrs.nasa.gov/citations/20090034988

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