Contrast vs Coil current
amplitude / offset · higher is better
Linewidth vs Coil current
2×HWHM (kHz) · lower is better
Figure of Merit vs Coil current
contrast × 10⁶ / (linewidth × 10³) · higher is better
Example Lorentzian fit @ 890 mA
best FoM = 13.5 ppm/Hz · R² = 0.9805