Sensitive imaging of electromagnetic fields with paramagnetic polar   molecules
  We propose a method for sensitive parallel detection of low-frequency electromagnetic fields based on the fine structure interactions in paramagnetic polar molecules. Compared to the recently implemented scheme employing ultracold $^{87}$Rb atoms [B{\"o}hi \textit{et al.}, Appl. Phys. Lett. \textbf{97}, 051101 (2010)], the technique based on molecules offers a 100-fold higher sensitivity, the possibility to measure both the electric and magnetic field components, and a probe of a wide range of frequencies from the dc limit to the THz regime. 
Sergey V. Alyabyshev, Mikhail Lemeshko, Roman V. Krems
physics.atom-ph cond-mat.quant-gas physics.chem-ph