CPT Cesium-Cell Atomic Clock Operation With a 12-mW Frequency Synthesizer ASIC

• Published in: Ieee Transactions On Instrumentation And Measurement (ISSN: 0018-9456), vol. 64, num. 1, p. 263-270
• Piscataway: Institute of Electrical and Electronics Engineers, 2015

In this paper, we present the design, fabrication, and electrical characterization of a low-power microwave source for interrogation of cesium atomic hyperfine transition frequency using the coherent population trapping (CPT) technique. The 4.6-GHz frequency generation and signal buffering is performed by a single-chip frequency synthesizer ASIC with a frequency tuning resolution of 1 x 10(-13) and a programmable RF output power from -10 to 0 dBm. The circuit was used to modulate the current of a vertical-cavity surface-emitting laser through a dedicated impedance matching network and low thermal conductivity transmission line. Strong modulation sidebands with >60% of carrier amplitude were obtained with an ASIC power consumption of 12 mW. The system was used as optical source for atomic interrogation in an experimental cesium CPT clock. The measured clock stability of 5 x 10(-11) at tau = 1 s, going down to 4.5 x 10(-12) at tau = 200 s, is limited by the signal-to-noise ratio of the detected CPT signal.

Keywords: Atomic clocks ; cesium ; frequency synthesizers ; microwave circuits ; phase locked loops (PLLs)

Reference

• EPFL-ARTICLE-205430
• doi:10.1109/Tim.2014.2329383
• View record in Web of Science

Record created on 2015-02-20, modified on 2017-05-10