Spatially Resolved Temperature Measurement Using Rydberg Doppler Broadening Thermometry
Year: 2026
Authors: Trivedi K.N., Carminati M., Cardona E.S., Bonaccorsi T., Donofrio R., Bygoc B., Morsch O.
Autors Affiliation: Univ Pisa, Dipartimento Fis E Fermi, Largo Pontecorvo 3, I-56127 Pisa, Italy; CNR INO, Via G Moruzzi 1, I-56124 Pisa, Italy; Univ Florence, Via Nello Carrara, I-50019 Florence, Italy; Swiss Fed Inst Technol, Prof Quanten Opt, HPF 20,Otto Stern Weg 1, CH-8093 Zurich, Switzerland; Univ Innsbruck, Inst Exper imentalphys, Technikerstr 25, A-6020 Innsbruck, Austria; Inst Quantenopt & Quanteninformat, Osterreich Akad Wissensch, Innsbruck, Austria; Sorbonne Univ, LTE former SYRTE, Observ Paris, Univ PSL,CNRS, LNE 61 Ave Observ, F-75014 Paris, France.
Abstract: We demonstrate a technique for spatially resolved temperature measurement utilizing Rydberg Doppler broadening thermometry. This method employs two focused laser beams arranged perpendicularly to excite laser-cooled atoms from the ground state to a Rydberg state via a two-photon absorption process. Temperature is obtained through Doppler broadening of the spectral line. The perpendicular configuration allows for selective probing of a specific position within the atomic cloud, enabling localized temperature measurement. This technique, in principle, offers a temperature resolution on the order of nK, attributed to the exceptionally narrow natural linewidth of the involved rubidium Rydberg transition line. Furthermore, the setup enables the measurement of position-velocity correlations within the cold atom ensemble. The velocity information is extracted through the Doppler shift, whereas the spatial information is inferred from the arrival time of ions detected by a channel electron multiplier detector. We use our method to measure the local temperature in a magneto-optical trap.
Journal/Review: PHYSICAL REVIEW LETTERS
Volume: 137 (11) Pages from: 113401-1 to: 113401-7
More Information: We gratefully acknowledge funding by the Julian Schwinger Foundation Grant No. JSF-18-12-00, the H2020 ITN MOQS (Grant Agreement No. 955479), and the PNRR MUR Project No. PE0000023-NQSTI.KeyWords: Field-ionization; Atoms; Spectroscopy; DensityDOI: 10.1103/kbfx-l9zk
