|
| |
FIZIKA A 12 (2003) 4 , 171 - 182
 
TEMPERATURE AND POWER-DEPENDENT MEASUREMENTS OF RbD2
TRANSITIONS BY DOPPLER-LIMITED AND DOPPLER-FREE SPECTROSCOPY
DIPANKAR BHATTACHARYYA, BIBHAS K. DUTTA, BISWAJIT RAY AND PRADIP N.
GHOSH
Department of Physics, University of Calcutta, 92, A. P. C. Road,
Calcutta - 700 009, India
e-mail: png@cubmb.ernet.in
Received 23 March 2003; revised manuscript received 17 September 2003
Accepted 29 September 2003 Online 19 April 2004
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.
PACS numbers: 42.62.Fi, 33.70.-w, 33.70.Jg
UDC 539.186
Keywords: diode laser spectroscopy, RbD2 transitions, temperature-dependent
line shape, saturation spectroscopy, hyperfine spectra
|
