Observation of continuous-wave on-resonance "self-focusing".
We report what to our knowledge are the first observations of an increase in the on-axis intensity of an intense cw on-resonance beam resulting from nonlinear absorption and diffraction during its propagation through a highly absorbing medium (sodium vapor). This "self-focusing" is not a self-lensing; instead it is modeled well by placing an aperture part way through the cell: The stripping by the aperture approximates the effect of the nonlinear absorption, and then Fresnel diffraction results in on-axis minima and maxima.
Tai
K
K
Gibbs
H M
HM
Rushford
M C
MC
Peyghambarian
N
N
Satchell
J S
JS
Boshier
M G
MG
Ballagh
R J
RJ
Sandle
W J
WJ
Leberre
M
M
Ressayre
E
E
Tallet
A
A
Teichmann
J
J
Claude
Y
Y
Mattar
F P
FP
Drummond
P D
PD