Nonlinear optical processes in a polydiacetylene measured with femtosecond duration laser pulses

Abstract

The temporal response of the third-order nonlinear optical susceptibility in poly bis( p-toluene sulfonate) of 2,4-hexadiyne-1,6 diol was determined by time-resolved degenerate four-wave mixing using tunable dye laser pulses with 300 fs duration. In the material’s absorption region these experiments were combined with saturated absorption techniques yielding a measurement for the excited state lifetime of 1.8 ps. Off resonance the nonlinear response was determined to be optical pulse width limited.