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From Stable Lasers to Optical-Frequency Clocks



John L. Hall, Jun Ye, L -. Ma, J L. Peng, M Notcutt, J D. Jost, A Marian


This is a report on behalf of the World Tema of Stable Laser and Optical Frequency Measurement Enthusiasts, even if most detailed illustrations draw mainly from our work at JILA. Specifically we trace some of the key ideas that have led from the first stabilized lasers, to frequency measurement up to 88 THz using frequency chains, revision of the Definition of the Metre, extension of coherent frequency chain technology into the visible, development of a vast array of stabilized lasers, and finally the recent explosive growth of direct frequency measurements capability in the visible using fs comb techniques. We present our recent work showing a Molecular Iodine -based Optical Clockwhich delivers, over a range of time scales, rF output at a stability level basically equivalent to the RF stability prototype, the Hydrogen Maser. We note the bifurcation between single-ion-based clocks - likely to be the stability/reproducibility ultimate winners in the next generation - simpler systems based on gas cells, which can have impressive stabilties but may suffer from a variety of reproducibility -limiting processes. Active Phase-Lock synchronization of independent fs lasers allows sub-fs timing control.
Symposium on Frequency Standards and Metrology


frequency stabilized laser, molecular-iodine optical clock, optical frequency measurement


Hall, J. , Ye, J. , Ma, L. , Peng, J. , Notcutt, M. , Jost, J. and Marian, A. (2008), From Stable Lasers to Optical-Frequency Clocks, Symposium on Frequency Standards and Metrology (Accessed June 14, 2024)


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Created October 16, 2008