Four-level N-scheme crossover resonances in Rb saturation spectroscopy in magnetic fields
Authors: Scotto S., Ciampini D., Rizzo C., Arimondo E.
Autors Affiliation: Laboratoire National des Champs Magntiques Intenses (UPR 3228, CNRS-UPS-UJF-INSA), 143 Avenue de Rangueil, 31400 Toulouse, France; Dipartimento di Fisica \”E. Fermi\”, Università di Pisa, Largo Bruno Pontecorvo 3, 56127 Pisa, Italy; INO-CNR, Via G. Moruzzi 1, 56124 Pisa, Italy; CNISM UdR, Dipartimento di Fisica \”E. Fermi\”, Università di Pisa, Largo B. Pontecorvo 3, 56127 Pisa, Italy
Abstract: We perform saturated absorption spectroscopy on the D-2 line for room temperature rubidium atoms immersed in magnetic fields within the 0.05-0.13 T range. At those medium-high field values the hyperfine structure in the excited state is broken by the Zeeman effect, while in the ground-state hyperfine structure and Zeeman shifts are comparable. The observed spectra are composed by a large number of absorption lines. We identify them as saturated absorptions on two-level systems, on three-level systems in a V configuration, and on four-level systems in an N or double-N configuration where two optical transitions not sharing a common level are coupled by spontaneous emission decays. We analyze the intensity of all those transitions within a unified simple theoretical model. We concentrate our attention on the double-N crossovers signals whose intensity is very large because of the symmetry in the branching ratios of the four levels. We point out that these structures, present in all alkali-metal atoms at medium-high magnetic fields, have interesting properties for electromagnetically induced transparency and slow light applications.
Journal/Review: PHYSICAL REVIEW A
Volume: 92 (6) Pages from: 063810 to: 063810
More Information: This research has been partially supported through NEXT (Grant No. ANR-10-LABX-0037) in the framework of the \”Programme des Investissements d\’Avenir.\” S.S. acknowledges financial support from Universite Franco Italienne, and E.A. acknowledges financial support from the Chair d\’Excellence Pierre de Fermat of the Conseil Regional Midi-Pyrenees. The authors acknowledge the valuable technical assistance of Nicola Puccini in realizing the magnetic assembly; the preparation by Nicolas Bruyant of the software recording simultaneously data from absorption, a FPI, and a wavemeter; and the support of Remy Battesti and Mathilde Fouche. E.A. is very grateful to Renaud Mathevet for sharing his atomic physics knowledge.DOI: 10.1103/PhysRevA.92.063810Citations: 6data from “WEB OF SCIENCE” (of Thomson Reuters) are update at: 2020-10-18References taken from IsiWeb of Knowledge: (subscribers only)Connecting to view paper tab on IsiWeb: Click hereConnecting to view citations from IsiWeb: Click here