Dy. Jeong et al., THE EFFECT OF THE LASER-ATOM INTERACTION TIME ON THE INFLUENCE OF VELOCITY-CHANGING COLLISIONS IN DOPPLER-FREE SPECTROSCOPY, Optics communications, 153(4-6), 1998, pp. 226-230
Remarkable reduction of the influence of velocity-changing collisions
in Doppler-free optogalvanic spectra has been achieved by using a squa
re pulse train produced by the intensity modulation of a cw ring dye l
aser in conventional intermodulated optogalvanic spectroscopy. Decreas
ing the pulsewidth and the repetition rate of the square pulse train,
the Gaussian collisional parameter, C, for the S-1(0) --> P-3(1) trans
ition of Yb atoms at low discharge current is reduced by two orders of
magnitude when compared to that of a conventional intermodulated opto
galvanic spectrum, The line narrowing of the Gaussian pedestals below
the theoretical limit was also observed. Reduction of the collisional
parameter as well as the line narrowing of Gaussian pedestals enhances
the spectral resolution of this method and allows measurements of hig
hly resolved Doppler-free spectra in hollow cathode discharge cells. (
C) 1998 Elsevier Science B.V. All rights reserved.