NIST’s Communications Technology Lab is developing a new paradigm for RF field sensing and measurements based on the atom. The Rydberg Atom-based RF Field Probes team is using highly excited alkali atoms to detect and measure electric fields from DC to daylight (from Hz to THz) with high sensitivity and fidelity. Due to the standard behavior of these atoms, this independent RF measurement method provides direct traceability to SI-defined constants.
Calibrated radio frequency (RF) electric field probes and antennas are currently limited by a complex, indirect traceability path and require a complex calibration – which presents a chicken-and-egg dilemma. Probes must be calibrated by placing them in a known electric field, while a precisely known electric field is only realized using calibrated probes. Borrowing a technique from atomic spectroscopy, electromagnetically-induced transparency (EIT), we can use atoms as a noninvasive field probe for directly SI-traceable, self-calibrated RF electric field measurements over a huge range frequency.
The Rydberg atom-based sensing technique has shown promise for many applications beyond RF field probe calibrations. We are currently exploring:
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