We solve the coupled mode equations governing the chalcogenide nonlinear fiber Bragg gratings (FBGs) numerically, and obtain the bistability characteristics. The characteristics of the chalcogenide nonlinear FBGs such as: switching threshold intensity, bistability interval and on-off switching ratio are studied. The effects of FBG length and its third order nonlinear refractive index on FBG cha...

in this work, we report, optical properties of cd1-xsnxte quantum dots (x= 0.05, 0.10 and 0.15) synthesized in water using thioglycolic acid (tga) as a modifier agent. the optical characterization of the samples was performed through absorption (uv) and photoluminescence spectra (pl). a red shift absorption and fluorescent emission peaks was observed which can be related to the increase of nano...

some issues; leakage, tunneling currents, boron diffusion are threatening sio2 to be used as a good gate dielectric for the future of the cmos (complementary metal- oxide- semiconductor) transistors. for finding an alternative and novel gate dielectric, the nio (nickel oxide) and pva (polyvinyl alcohol) nano powders were synthesized with the sol-gel method and their nano structural properties w...