اندازه‌گیری ضرایب نوری غیرخطی شیشه‌های چلکاجنید به روش جاروب- z و روش ترکیب چهار موج تبگهن DFWM

Chalcogenide glasses such as arseic sulfide(As2 S3 ) have attracted attention for applications such as all-optical switching in high speed communication. This is due to their high non-linear refractive-index. Z-scan and the Degenerate four wave mixing (DFWM) techniques can be used to measure the non-linear refractive index n 2 and the two photon absorption coefficient β . A simaltanous closed-aperture and open-aperture Z-scan experimental set up was used to obtain the experimental results. The results were then fitted into a theoretical formula. Values of n2=3×10-17m2/W and β= 0.29 cm/GW have been obtained. DFWM measurements were made on arsenic sulfide films. A Box-cars forward geometry was used in these measurements. Experimental results based on non-phase matched signals were again fitted into a theoretical formula and a value of n2 =3.9×10-17 m2 /W was obtained .