Sub-Wavelength Microwave Electric Field Imaging using Rydberg Atoms

It is clearly important to pursue atomic standards for quantities like electromagnetic fields, time, length and gravity. We have recently shown that Alkali atoms in a vapor cell can serve as a standard for microwave electric field strength and that vector electrometry is also feasible. Here, we demonstrate, for the first time, that microwave electrometry using Rydberg atom electromagnetically induced transparency can be used to image microwave microwave electric fields with unprecedented precision. The spatial resolution of the method is sub-wavelength $\lambda$/1933. We present new data demonstrating the utility of the method. Our calculations using High Frequency Structural Simulator (Hfss) agree well with the pattern of the field measured by our experiment.