An Optical Clock Based on Coherent Population Trapping of Alkaline-earth Ions

2009/04/02 by Z. H. Lu, Lu, Z. H., L. J. Wang +1
Physics and Astronomy · #Advanced Frequency and Time Standards #Atomic Physics (physics.atom-ph) #Atomic and Subatomic Physics Research #FOS: Physical sciences #Optics (physics.optics) #Quantum optics and atomic interactions

paper · pdf · doi:10.48550/arxiv.0904.0285

openalex publication_date 2009/04/02 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

Abstract

An ultra-stable optical clock based on coherent population trapping effect of alkaline-earth ions, such as Ca⁺, Sr⁺, Ba⁺, is analyzed here. The proposed transitions use the odd isotopes, so that the frequency shift is insensitive to the applied magnetic field. To enhance the signal, a large number of ions are trapped in a linear Paul trap, and laser cooled to crystallize such that the ions are in the Lamb-Dicke regime to avoid first order Doppler shift. Other relevant frequency shifts are also analyzed. Further techniques to improve the stability of the clock signal are discussed.

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