Simultaneous sensing axial and radial magnetic fields based on weak measurement

We propose a method for sensing the non-specific orientation magnetic field based on a simple frequency domain weak measurement system. The magnetic fields with different directions and magnitudes induce the phase differences. It experimentally and theoretically demonstrates the high sensitivity of the system to phase differences, which confirms the potential of detecting magnetic fields. We obtain a sensitivity of 1.19 nm/mT and a resolution of 0.70 × 10−3 mT. Further, the axial and radial magnetic fields can be calculated simultaneously by using the characteristics of the central wavelength and intensity of the spectrum. The method has a simple set-up and offers high sensitivity, real-time response to the magnetic field, suggesting a new way of enriching the detection of the vector magnetic field.