Figure 7.

Impedance analysis requires a determination of the entire admittance trace (full and dashed lines), which takes time. Fast measurements can build on the conductance, $G_{\mathrm{el}}$, and the susceptance, $B_{\mathrm{el}}$, at one single frequency close to the center of the resonance, $f_{\mathrm{c}}$. Shifts in $G_{\mathrm{el}}$ and $B_{\mathrm{el}}$ are converted to shifts in $f_{\mathrm{res}}$ and Γ (blue arrows). As the top panel shows, a shift in resonance frequency changes $B_{\mathrm{el}}$, but leaves $G_{\mathrm{el}}$ unchanged. Conversely, an increase in bandwidth lowers $G_{\mathrm{el}}$, but leaves $B_{\mathrm{el}}$ unchanged (bottom).