The dips become more pronounced if the Rabi frequencies are increased or if $\gamma_{g,m}$ is decreased. Figure \[fig:EOM\](b) shows that for $\omega_\text{EOM}=\Gamma/4$, the scattering rate is maximized for the modulation amplitude $\Phi_\text{EOM} \approx 1.4\pi$. At lower amplitudes the polarization variation is not sufficient to fully destabilize the dark states, and at higher amplitudes an increasing part of the repumper intensity is transferred into sidebands further from resonance.

![\[fig:EOM\] Quasi-steady-state scattering rate (a) as a function of modulation frequency $\omega_\text{EOM}$ for $\Phi_\text{EOM}=\pi$ and (b) as a function of modulation amplitude $\Phi_\text{EOM}$ for $\omega_\text{EOM}=\Gamma/4$. $\Omega_\mathrm{c} = \Omega_\mathrm{r} = \Gamma$, $\delta_\mathrm{c} = -\Gamma/2$, $\delta_\mathrm{r} = \Gamma/2$, $\gamma_{g,m}=\Gamma/10$, cooling laser $\mathbf{u}_x$ polarized, and repumper as in Eqs. (\[eq:EOM-pol\]) and (\[eq:EOM-ret\]).](Fig09-EOM3){width="1\columnwidth"}

Ion motion
==========

The ion undergoes both secular (thermal) motion at the trap frequencies and micromotion at the applied trap drive frequency. If the ion is not significantly perturbed from the RF voltage symmetry node of the trap by stray fields so that the micromotion amplitude is kept low, the Doppler cooling is not compromised and the ion experiences an approximately constant laser intensity near the beam focus. Under these circumstances, the motion can be accounted for by considering the rest frame of the 