Influence of doping on the photorefractive properties of a polymer-dispersed liquid crystal

Redler, Andreas; Kitzerow, Heinz-S.
November 2008
Applied Physics Letters;11/3/2008, Vol. 93 Issue 18, p183304
Academic Journal
The photorefractive effect is studied in a photoconducting polysiloxane containing small droplets of a low molar mass liquid crystal. In order to vary the trap density for charge carriers, the system is doped with tetramethyl-phenylendiamine. The measured energy transfer from one beam to the other (two-beam coupling) indicates a high gain coefficient, which is enhanced by adding small concentrations of the dopant. Measurements of the phase and the amplitude of the refractive index modulation confirm that this behavior can be attributed to an increase in the trap density.


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