Abstract
Polydiacetylene microcrystals in a water suspension or a polymer matrix were prepared by a simple precipitation procedure in order to obtain a thin samples with good optical quality maintaining the characteristics of crystalline materials. The nonlinear refraction, n2, and nonlinear absorption, ß, around the exciton peak were measured by z-scan method using a tunable picosecond laser. The signs of the n2 are positive/negative at wavelengths shorter/longer than the exciton peak and strong saturable absorption, which ß is negative, are observed around the peak. The largest n2 was obtained to be plus 0.024 cm2/GW (Re ?(3) = +1.4 × 10-9 esu) at 640 nm for a gelatin composite film containing 24 wt percent of polydiacetylene microcrystals. ©2005 Copyright SPIE - The International Society for Optical Engineering.
Original language | English |
---|---|
Pages (from-to) | 241-248 |
Number of pages | 8 |
Journal | Proceedings of SPIE - the International Society for Optical Engineering |
Volume | 2998 |
DOIs | |
Publication status | Published - 1997 |
Event | Photosensitive Optical Materials and Devices - San Jose, CA, United States Duration: 12 Feb 1997 → 12 Feb 1997 |
Keywords
- Nonlinear absorption
- Nonlinear refractive index
- Organic microcrystal
- Polydiacetylene
- Z-scan method