Samoc, MarekSamoc, AnnaLuther-Davies, BarryDiez, IsabelSchulz, Burkhard2015-12-071542-1406http://hdl.handle.net/1885/20302We describe experimental studies of cubic nonlinear optical properties performed in reflection mode on thin films of polyaniline. It is shown that pump-probe and degenerate four-wave mixing reflection techniques are sensitive enough to obtain readily detectable nonlinear optical signals from polyaniline with femtosecond pulses at light intensities on the order of 100 GW/cm 2. The results are compared with previous studies indicating that nonlinear coefficients of polyaniline are in the range of |n 2 | = 10 -12 -10 -11 cm 2 /W and that the relaxation of the nonlinear effects involves picosecond range processes.Keywords: Amines; Laser pulses; Nonlinear optics; Optical properties; Refractive index; Relaxation processes; Thin films; Degenerate four-wave mixing; Nonlinear refractive index; Polyaniline; Pump-probe; Organic polymers Degenerate four-wave mixing; Nonlinear refractive index; Polyaniline; Pump-probeCubic Nonlinear Optical Properties of n-Conjugated Polymers from Reflection-Mode Measurements200610.1080/154214005003830062015-12-07