Novel atomic and molecular systems for radiative thermometry

Radiative (non-contact) thermometry currently relies on classical radiation detectors, which are typically calibrated through long traceability chains that require constant upkeep. These requirements have posed a variety of problems in fields like remote sensing, where constant recalibration of detectors is not possible. Instead, we are attempting to realize standards for radiative thermometry based on either Rydberg atoms or polar molecules. For the former, we are pursuing multiple measurement techniques, including thermal radiation induced state transfer and Stark shifts in both rubidium and ytterbium atoms. These systems are most sensitive to thermal radiation in the microwave (10 GHz to 1 THz) regimes and can potentially produce new radiation probes for climate monitoring, weather prediction, and more accurate mobile atomic clocks, among other applications. For the latter, we are pursuing laser-cooled MgF molecules, which would be sensitive in the near-IR. MgF offers several advantages for laser cooling, including larger optical forces, large accelerations, and high capture velocities. When combined, MgF offers the potential for a large number of trapped molecules, enhanced sensitivity, and a new radiometric standard traceable directly to the SI.