Theoretical analysis of all-optical spatial light modulation in organometallics based on triplet state absorption dynamics

We present a general theoretical analysis of all-optical spatial light modulation in organometallic compounds based on nonlinear excited-state absorption, considering the propagation effects of both read and write beams. A detailed analysis for Pt:ethynyl complex has been presented based on the rate equation approach and an analytical solution for the write beam transmission has been obtained. For typical values, the read beam at 633 nm is modulated by 97.9% with a write beam intensity of 100 kW/cm2 at 355 nm. It is shown that the effect of write beam propagation in the medium is appreciable at low write beam intensities and the percentage modulation in Pt:ethynyl complex is larger than that in C60 in toluene and ZnTPP. The characteristics have also been used to design all-optical NOT and the universal NOR and NAND logic gates.