A magnetometer based on coherent population beating

We proposed a novel magnetic field measurement method extended from the CPT method. It is based on the coherent population beating (CPB) phenomenon. CPB occurs in a typical three-level system, when the frequency difference of the two pump laser fields have a detuning from the ground states splitting, and the CPB oscillation frequency is equal to the detuning. We are able to detect the beat frequency shift with the external magnetic field changing via digital processing, thus we can acquire the Zeeman frequency shift and then calculate external magnetic field intensity accurately.