Joshua A. Gordon, Christopher L. Holloway, Matthew T. Simons
We present a technique which shows great promise for realizing an atomic standard measurement of RF fields that is intrinsically calibrated, directly linked to the SI and atomic structural constants. This technique relies on the reponse of Rydberg atoms to radio frequency (RF) electric-field measurements. The rich resonance response of these atoms occurs across a large frequency range from tens of MHz and approaching 1 THz. Alkali atoms such as rubidium (Rb) and cesium (Cs) confined in a glass vapor cell are optically excited by two different lasers to high energy Rydberg states. Once in the Rydberg state the atoms exhibit a significant response to RF fields which alters the optical spectrum of the atoms. The RF field strength is then directly obtained from the optical spectrum. We discuss the theory behind this technique. Measurements in the far-field of a standard gain horn antenna as well as a coplanar waveguide mode are made. A newly developed quantum electric-field probe based on this Rydberg atom technique, and which is constructed from a fiber optically coupled vapor cell is used for these measurements.
, Holloway, C.
and Simons, M.
Rydberg Atom Electric-Field Metrology, 90th ARFTAG Conference, Boulder, CO, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=924452
(Accessed October 23, 2021)