High Sensitivity Optically Pumped Quantum Magnetometer
Figure 7
Measured in-phase component (a); quadrature component (b) and phase shift (c) between the photo diode output and the driving rf magnetic field. All signals were measured in a magnetically unshielded environment by continuously sweeping the driving rf frequency along the resonance frequency over a 6-second time range. It is important to note that the magnetically induced 50 Hz interference signal was suppressed by a notch filter. The input optical power was 20 μW and the vapor cell temperature 48°C. The HWHM bandwidth is highlighted for each measured output signal.
