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Exponential scaling of clock stability with atom number



Till P. Rosenband, David R. Leibrandt


In trapped-atom clocks, the primary source of decoherence is often the phase noise of the oscillator. In this case, it is theoretically possible to derive exponential performance gains by combining several atomic ensembles. For example, M ensembles of N atoms can be combined with a variety of probe periods, to derive a clock stability whose variance is reduced by a factor of 2^(1−M) (M/2) from that of standard Ramsey clocks with the same number of atoms MN when N>=36. The ensembles with reduced frequency or probe period are responsible only for counting the integer number of 2 pi phase wraps, and do not affect the clock's systematic errors.
Physics Arxiv


Atomic clock, Quantum metrology, Quantum phase estimation


Rosenband, T. and Leibrandt, D. (2015), Exponential scaling of clock stability with atom number, Physics Arxiv (Accessed April 12, 2024)
Created March 28, 2015, Updated February 19, 2017