Ultranarrow faraday rotation filter at the rb d1 line
Joanna A. Zielińska, Federica A. Beduini, Nicolas Godbout +1 more
We present a theoretical and experimental study of the ultra-narrow bandwidth Faraday anomalous dispersion optical filter (FADOF) operating at the rubidium D1 line (795 nm). This atomic line gives better performance than other lines for the main FADOF figures of merit, e.g. simultaneously 71 % transmission, 445MHz bandwidth and 1.2GHz equivalent noise bandwidth. c © 2013 Optical Society of America OCIS codes: 020.1335, 010.3640 Ultra-narrow bandwidth optical filters are key el-ements in laser remote sensing (LIDAR), observa-tional astronomy, free-space communications and quan-tum optics. Relative to conventional interference fil-ters, FADOFs offer high background-rejection, mechani-cal robustness, imaging capability and high transmission. FADOFs have been developed for several alkali atom res-onances – Cs D2 [1] and 6S1/2 → 7P3/2 [2] lines, Rb D2 line [3, 4], K (three lines) [5], Na D lines [6], and for Ca [7]. We demonstrate a FADOF on the D1 line of Rb (wave-length 795 nm). This line, efficiently detected with Si detectors, accessible with a variety of laser technolo-gies, and with large hyperfine splittings, is a favorite for coherent and quantum optics with warm atomic va-pors. Applications include electromagnetically-induced transparency [8], stopped light [9], optical magnetom-etry [10, 11], laser oscillators [12], polarization squeez-ing [13, 14], quantum memory [15] and high-coherence heralded single photons [16,17]. Here we show that the Rb D1 line provides supe-rior FADOF performance. We demonstrate a FADOF surpassing other atoms and other Rb transitions for key figures of merit, including peak transmission Tmax, transmission bandwidth and equivalent noise bandwidth ENBW = T−1max T (ν)dν, where T (ν) is the filter trans-mission versus frequency ν [4].
•Jan 1, 2012•87 citations