Fig. 3: Summary of the experimental setup for the compound clock demonstration.
From: Dynamical decoupling of laser phase noise in compound atomic clocks
a Frequency sensitivity g(t) of regular Ramsey spectroscopy22,23 (red line) and of the decoupled protocol (blue line). The increased sensitivity of the latter during each of the M = 16 flip pulses gives rise to imperfections of the dynamical decoupling (see main text and “Methods”). b Line shape of Ramsey spectroscopy (red line) and the decoupled protocol (blue line), scaled to a contrast of 0.75. The signals observed while scanning the laser across resonance in the absence of artificial frequency noise are shown for comparison (red diamonds, blue circles). Note that the Ramsey scan (red diamonds) was recorded for a slightly different dark time (500 ms) than used in the experiment. c Single-sided power spectral density (PSD) Sy(f) of the artificial laser noise imprinted onto the interrogation laser (blue line). The phase noise of our interrogation laser system as reported in ref. 15 is shown schematically for comparison (green line). d Distributions of final phase deviations due to artificial frequency noise (blue) and intrinsic laser noise (green) after the interrogation time.
