Publication in Metrologia
On-line estimation of local oscillator noise and optimisation of servo parameters in atomic clocks
Ian D Leroux, Nils Scharnhorst, Stephan Hannig, Johannes Kramer, Lennart Pelzer, Mariia Stepanova, and Piet O Schmidt
For atomic frequency standards fluctuations of the local oscillator is one of the dominant noise sources. We investigate the role of the servo algorithm used to stabilise the local oscillator and derive an optimal linear prediction algorithm.
Using simple analytical models and numerical simulations, we establish optimum probe times as a function of clock atom number and of the dominant noise type in the oscillator. We calculate the resulting local oscillator-dependent scaling of achievable clock stability with atom number for product states as well as for maximally-correlated states.