LASER PHYSICS: STUDY RESULTS FROM A. SARGSYAN ET AL PROVIDE NEW INSIGHTS INTO LASER PHYSICS
Science Letter
July 29, 2008
According to recent research published in the journal Laser
Physics, "It is demonstrated that the velocity-selective optical
pumping/saturation resonances of the reduced absorption in a Rb vapor
nanocell with thickness L = lambda, 2 lambda, and 3 lambda (resonant
wavelength lambda = 780 nm) allow for the complete elimination of
crossover (CO) resonances. We observe well-pronounced resonances
corresponding to the F-g = 3 & rarr; F (e) = 2, 3, and 4 hyperfine
transitions of the Rb-85 D-2 line with line widths close to the
natural width."
"A small CO resonance located midway between F-g = 3 & rarr; F-e =
3 and F-g = 3 & rarr; F-e = 4 transitions appears only for L>= 4
lambda. The D-2 line (lambda = 852 nm) in a Cs nanocell exhibits a
similar behavior," wrote A. Sargsyan and colleagues (see also Laser
Physics).
The researchers concluded: "From the amplitude ratio of the CO and VSOP
resonances, it is possible to determine the thickness of the column
of alkali vapor in the range of 1-1000 mu m. The absence of the CO
resonances for nanocells with L similar to lambda is attractive for
the frequency reference application and for studying the transitions
between the Zeeman sublevels in external magnetic fields."
Sargsyan and colleagues published their study in Laser Physics
(Saturated absorption spectroscopy: Elimination of crossover resonances
with the use of a nanocell. Laser Physics, 2008;18(6):749-755).
For additional information, contact A. Sargsyan, National Academy
Science Armenia, Institute Physics Research, Ashtarak 0203, Armenia.