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Atom-Based RF Electric Field Metrology: From Self-Calibrated Measurements to SubWavelength and Near-Field Imaging



Christopher L. Holloway, Matthew T. Simons, Joshua A. Gordon


We discuss a fundamentally new method for electric (E) field metrology. This new approach is significantly different than currently used field measurement techniques in that it is based on the interaction of radio-frequency (RF) fields with Rydberg atoms (alkali atoms placed in a glass vapor cell are excited optically to Rydberg states). The applied RF-field alters the resonant state of the atoms. The Rydberg atoms act like an RF-to-optical transducer, converting an RF E-field to an optical-frequency response. The RF probe utilizes the concept of Electromagnetically Induced Transparency (EIT) and Autler-Townes splitting. The RF transition in the four-level atomic system causes a split of the EIT transmission spectrum for a probe laser. This splitting is easily measured and is directly proportional to the applied RF field amplitude. The significant dipole response of Rydberg atoms enables this technique to make self-calibrating measurements over a large frequency band including 1~GHz to 500~GHz. In this paper, we report on our results in the development of this metrology approach. We also discuss key applications: that is, self-calibrated measurements, millimeter-wave and sub-THz measurements, and sub-wavelength imaging and field mapping.
IEEE Transactions on Electromagnetic Compatibility


atom based metrology, Autler-Townes splitting, broadband sensor and probe, electrical field measurements and sensor, electromagnetically induced transparency (EIT), sub-wavelength imaging, Rydberg atoms


Holloway, C. , Simons, M. and Gordon, J. (2017), Atom-Based RF Electric Field Metrology: From Self-Calibrated Measurements to SubWavelength and Near-Field Imaging, IEEE Transactions on Electromagnetic Compatibility, [online], (Accessed May 31, 2023)
Created April 1, 2017, Updated January 27, 2020