Picosecond all-optical logic gate in a nonlinear organic étalon

Abstract

An all-optical logic gate has been demonstrated in a nonlinear organic étalon using femtosecond laser pulses. The logic gate consists of a guest-host organic thin film, 7-[4-[(4-hexyloxyphenyl)azo](naphthyl)azo-(2,3-dihydro-1,3-dimethyl-2-octyl)] perimidine doped in poly(methyl methacrylate), sandwiched between two highly reflective mirrors. It shows a subpicosecond switch-on time and a switch-off or recovery time that has a fast, ≂4 ps component and slower components. A maximum contrast ratio of ≂2 between the switch-on and switch-off states of the optical gate was obtained. The nonlinear index of refraction is also measured from this Fabry–Perot interferometer to be Δn=0.005.