Nanostructured polymeric optical limiter materials

Characterization of dye-doped polymer films for polymer 1D photonic crystals

“…For these measurements, the output of a Ti:sapphire regenerative amplifier (771 nm, 1 kHz rep. rate, 150 fs TFwHm, Clark MXR CPA-2001) was used to excite the sample and also to produce a white light continuum (WLC) in sapphire to probe the sample at various time delays from -100 picoseconds to 2.4 nanoseconds after excitation. A change in absorption can be related to a change in refractive index (An) by the nonlinear Kramers-Kr6nig relationship [4] in the following manner: An(oP;e Ie )= c A a ( ;we,!edQ (2) where wp and We is the frequency o mce of the pump, c is the speed of light, and p' is the principle value. The nonlinear Kramers-Kr6nig relationship has the advantage over the linear analog because Act is confined over a finite wavelength interval and therefore gives the shape and magnitude of An [5].…”

“…PbPc(CP)4 was chosen because it has a strong and broad excited-state absorption band in the visible coupled with a long excited-state lifetime (> 10 nanoseconds). Polycarbonate was chosen as the host polymer due to its optical clarity and the ability to dope the polymer with up to 25% by weight of PbPc(CP)4 with limited dye aggregation using a method previously described [2].…”

The refractive index of dye/polymer composite films

“…PbPc(CP) 4 is a typical representative of an important class of nonlinear dyes that possess a strong and broad excited-state absorption band in the visible coupled with a long excited-state lifetime (> 10 nanoseconds) [1]. A polycarbonate was chosen as the host polymer due to its optical clarity and the ability to dope the polymer with up to 20% by weight of PbPc(CP) 4 using a method previously described [2]. The refractive index of polymer/dye composites with up to ~20 weight percent dye were measured at six wavelengths between 473 nm and 1546 nm.…”