Figure 4

Comparison between the linear spectral densities (LSD) of the readout of the NV sensor in single hyperfine driving regime (red line) and in the simultaneous hyperfine driving (black line). The linear spectral density of the read-out with the detector blocked(green line), with the input of the LIA disconnected (blue line) and the Continous Wave(CW)-shot noise (dark green dashed line) are also shown. The value of the low-frequency plateau gives the magnetic sensitivity of the measurement. The simultaneous hyperfine driving improvement the sensitivity of a factor ≈ 1.5