%0 Journal Article
%K measurement
%K transmission
%K beam
%K picosecond
%K spectra
%K spectrum
%A M. M Cynthia Hipwell
%A Chang-Lin Tien
%A Xianglei Mao
%A Richard E Russo
%B Experimental Heat Transfer
%D 1998
%G eng
%N 4
%P 281-297
%R 10.1080/08916159808946566
%T The dual beam picosecond continuum technique for measurement of short time-scale transmission spectra
%V 11
%2 LBNL-43857
%8 04/1998
%) Laser
%X <p>In this work, a dual-beam measurement technique is presented to measure the short-time-scale optical properties of novel materials. It is shown that the picosecond continuum probe source obtained from nonlinear interaction with H<sub>2</sub>O/D<sub>2</sub>O is highly variable and does not permit detection of small changes in absorption /transmission spectra. The dual-beam approach is proposed to allow simultaneous measurement of a sample's properties in both the excited and steady states. As an example, the technique is applied to the picosecond transmission spectrum of light-emitting porous silicon. Photo-induced absorption is observed at a level that could not be detected without the new technique.</p>