A. Reuther et al., A SIMPLE METHOD FOR THE IN-SITU ANALYSIS OF FEMTOSECOND UV PULSES IN THE PUMP-PROBE SPECTROSCOPY OF SOLUTIONS, Optics communications, 141(3-4), 1997, pp. 180-184
It is shown that the two-photon absorption (TPA) process in water and
other solvents can be applied in common pump-probe experiments for the
in situ determination of the peak intensity and duration of femtoseco
nd pump pulses. The TPA coefficient of liquid water for femtosecond ir
radiation at 282 nm is measured to be beta(282 nm + 282 nm) = (1.9 +/-
0.5) x 10(-12) m/W. The coefficient for simultaneous absorption of ph
otons at 282 nm and 299 nm is determined to be beta(282 nm + 299 nm) =
(1.0 +/- 0.4) x 10(-12) m/W. Various TPA coefficients of thin diamond
samples an also reported for pump pulses at 282 nm and probing pulses
in the range 282-750 nm that art useful for the estimation of pulse i
ntensities. The described technique is especially advantageous for the
transient spectroscopy of solutes. (C) 1997 Published by Elsevier Sci
ence B.V.