Technical limits of sensitivity for EIT magnetometry.

Optical magnetometers based on electromagnetically induced transparency (EIT) in atomic vapor can in principle achieve outstanding sensitivity and accuracy in a small volume. Up until now, however, the predicted fundamental quantum-noise-limited sensitivity has not been achieved in practice due to various technical limitations associated with the measurement apparatus. Here we analyze these restrictions and propose viable mitigation strategies for performance optimization. As an example, we show that an EIT magnetometer can theoretically achieve sensitivity better than 100 fT at 1 s measurement time under realistic conditions.