L. Marquez et al., HIGH-PUMP-POWER EFFECTS ON RESONANT NEARLY DEGENERATE 4-WAVE-MIXING SIGNAL FOR HOMOGENEOUSLY AND INHOMOGENEOUSLY BROADENED 2-LEVEL SYSTEMS, Physical review. A, 47(5), 1993, pp. 4185-4192
The influence of the high-pump-field intensity saturation and dynamic
Stark effects on the resonant nearly degenerate four-wave-mixing signa
l (omega3 = 2omega1 - omega2) is studied in a frequency space defined
by the pump- and probe-field frequencies, omega1 and omega2, respectiv
ely. Variable inhomogeneous widths have been considered ranging from e
xtremely narrow (homogeneous distribution) to extremely wide. Remarkab
le differences between nearly homogeneously broadened systems and extr
eme inhomogeneous ones are exhibited. It is shown, for the situation o
f homogeneous broadening, that the spectra carried on with fixed probe
and fixed pump frequency values have substantial differences in shape
. These differences disappear in the situation of extreme inhomogeneou
s broadening. Fixed-pump-frequency resonant and fixed-probe-frequency
nonresonant spectra are proposed as very convenient tools to yield use
ful evidence about the width of the inhomogeneous molecular distributi
on.