Figure 3
From: A Single-Ion Reservoir as a High-Sensitive Sensor of Electric Signals
Radiofrequency force sensing. Upper: ρ z,max as a function of (ω dip − ω z )/2π for two amplitudes V dip of the time-varying dipole field and different oscillation frequencies. The laser beams are always interacting with the ion. The analytical fit is carried out using Eq. (3), while the numerical fit takes into account the anharmonicity. Middle left: zoomed plot showing the data taken for ω z = 2π × 108 kHz for different amplitudes, i.e., V 2 ≈ 125 μVpp and V 3 = 0.7V 2, and different laser parameters, resulting in γ z,2 = 88(2) Hz and γ z,3 = 298(24) Hz, respectively, from the analytical fit. Middle right: sensitivity of the ion reservoir to electric forces in neV/μm. * shows the field generated by a single-charged ion oscillating in a second trap, and ** the field generated by e.g. 50 antiprotons or 50 single-charged superheavy-element ions. The lower right side of the figure, shows the variance of the ion distribution as a function of (ω dip − ω z )/2π for an amplitude V 4 = 0.1V 2. The cyan-colored area shows the noise level, which is defined by the average variances of the distributions off resonance. Since the invariance for each data point is obtained directly from the Gaussian fit to the projection of the fluorescence into the axial direction, the uncertainty of each data point is the quadratic sum of the statistical and systematic uncertainties, the first provided by the fit and the second by the observed variations.
