E-Field Strength Measurement using Rydberg Atom Based sensor for Microwave Metrology

In this work, the theoretical and measurement results have been reported of microwave E-field sensing using an atomic spectroscopy instead of conventional methods (using antennae) under practice till date. This method is based on interaction of microwave with the Rb atoms excited to the Rydberg states by using two laser beams. This significantly new technique may get accepted internationally as a new primary standard for accurate and precise measurements of various Radio-Frequency parameters such as E-field, power, radiation pressure etc as it provides traceability to physical constants and SI units. The atomic model is also studied theoretically and Optical Bloch equations of the same are reported. It has been shown that microwave E-field strength is measured by studying the frequency difference between the peaks in laser transmission curve. The ability of atoms to sense E-field is shown by varying the power and distance of the antenna from atomic cell. In addition, results are shown for weak RF field detection by detuning the RF field by MHz order.