Original scientific paper
Temperature and power-dependent measurements of Rb D2 transitions by Doppler-limited and Doppler-free spectroscopy
Dipankar Bhattacharyya
; Department of Physics, University of Calcutta, 92, A. P. C. Road, Calcutta - 700 009, India
Bibhas K. Dutta
; Department of Physics, University of Calcutta, 92, A. P. C. Road, Calcutta - 700 009, India
Biswajit Ray
; Department of Physics, University of Calcutta, 92, A. P. C. Road, Calcutta - 700 009, India
Pradip N. Ghosh
; Department of Physics, University of Calcutta, 92, A. P. C. Road, Calcutta - 700 009, India
Abstract
An external-cavity diode-laser spectrometer has been set up for high-resolution measurement of line shapes of the RbD2 transitions. Temperature-dependent fine-structure measurements are carried out in a free-running temperature condition by using frequency ramps for repetitive current tuning over a region of 17 GHz, encompassing all of the four Doppler broadened transitions of the two isotopes in an almost collision-free region. The Doppler broadened widths extracted from temperature-dependent line shapes, on least squares fitting to observed data, lead to an estimation of root-means-square velocities of vapour atoms under varying temperature conditions. Saturated-absorption spectroscopic measurements show complete resolution of the hyperfine Lamb dips and crossover resonance dips of one 87RbD2 transition. Data recorded from power-dependent measurement of one of unresolved 85RbD2 transitions are analyzed to obtain the saturation parameter and power broadening coefficient. The linewidths of different fully resolved Lamb dips of the hyperfine and crossover-resonance components are not the same, suggesting differences in their natural linewidths.
Keywords
diode laser spectroscopy; RbD2 transitions; temperature-dependent line shape; saturation spectroscopy; hyperfine spectra
Hrčak ID:
301645
URI
Publication date:
1.10.2003.
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