Sensitivity of a vector atomic magnetometer based on electromagnetically induced transparency.

We present a realization of a magnetic sensor based on electromagnetically induced transparency (EIT) resonances observed in hot Rb vapor using lin∥lin polarized dichromatic light and evaluate scalar and vector capabilities of the sensor for measuring Earth-like magnetic fields. We demonstrate scalar measurement sensitivity of 2 / in the 1-100 Hz spectral frequency band using a ~1 cm Rb vapor cell, significantly improving the performance for such a configuration if compared with earlier measurements of large magnetic fields. By using a single linearly polarized dichromatic optical field, we are also able to determine the direction of the magnetic field with respect to the light propagation direction and polarization, taking advantage of the symmetries of the interaction scheme.

Application of kernel principal component analysis for optical vector atomic magnetometry.

Vector atomic magnetometers that incorporate electromagnetically induced transparency (EIT) allow for precision measurements of magnetic fields that are sensitive to the directionality of the observed field by virtue of fundamental physics. However, a practical methodology of accurately recovering the longitudinal angle of the local field through observations of EIT spectra has not been established. In this work, we address this problem of angle determination with an unsupervised machine learning algorithm utilizing nonlinear dimensionality reduction.

Magnetic communication by polarization helicity modulation using atomic magnetometers.

The radio frequency telecommunication at a kilohertz range through an electrically conductive medium is often impeded by the strong reflection and absorption at the interface. The polarization helicity of the magnetic field can be modulated/demodulated to provide a new communication protocol to potentiality circumvent these issues. Here, a miniature magnetic quantum receiver, capable of simultaneously discriminating the two possible helicities of a magnetic field, is presented.