Broadband Rydberg Atom-Based Electric-Field Probe for SI-Traceable, Self-Calibrated Measurements

TLDR: In this article, the authors proposed an approach for the measurement of electric fields based on the interaction of radio frequency (RF) fields with alkali atoms excited to Rydberg states via the Autler-Townes effect and detect the splitting via electromagnetically induced transparency.

Abstract: We discuss a fundamentally new approach for the measurement of electric fields that will lead to the develop- mentofabroadband,directSI-traceable,compact,self-calibrating -field probe (sensor). This approach is based on the interaction of radio frequency (RF) fields with alkali atoms excited to Rydberg states. The RF field causes an energy splitting of the Rydberg states via the Autler-Townes effect and we detect the splitting via electromagnetically induced transparency. In effect, alkali atoms placed in a vapor cell act like an RF-to-optical transducer, converting an RF -field strength measurement to an optical frequency measurement. We demonstrate the broadband nature of this approach by showing that one small vapor cell can be used to measure -field strengths over a wide range of frequencies: 1 GHz to 500 GHz. The technique is validated by comparing experimental data to both numerical simulations and far-field calculations for various frequencies. We also discuss various applications, including: a direct traceable measurement, the ability to measure both weak and strong field strengths, compact form factors of the probe, and sub-wavelength imaging and field mapping. Index Terms—Atom based metrology, Autler-Townes splitting, broadband sensor and probe, electrical field measurements and sensor, electromagnetically induced transparency (EIT), Rydberg atoms, sub-wavelength imaging.