Photosensitive and thermal nonlinear effects in chalcogenide photonic crystal cavities

作者：Lee Michael W^*; Grillet Christian; Monat Christelle; Maegi Eric; Tomljenovic Hanic Snjezana; Gai Xin; Madden Steve; Choi Duk Yong; Bulla Douglas; Luther Davies Barry; Eggleton Benjamin J

来源：Optics Express, 2010, 18(25): 26695-26703.

DOI：10.1364/OE.18.026695

We investigate the photosensitive and thermo-optic nonlinear properties of chalcogenide glass photonic crystal (PhC) cavities at telecommunications wavelengths. We observe a photosensitive refractive index change in AMTIR-1 (Ge(33)As(12)Se(55)) material in the near-infrared, which is enhanced by light localization in the PhC cavity and manifests in a permanent blue-shift of the nanocavity resonance. Thermo-optic non-linear properties are thoroughly investigated by i) carrying out thermal bistable switching experiments, from which we determined thermal switching times of 63 mu s and 93 mu s for switch on and switch off respectively and ii) by studying heating of the cavity with a high peak power pulsed laser input, which shows that two-photon absorption is the dominant heating mechanism. Our measurements and analysis highlight the detrimental impact of near-infrared photosensitivity and two-photon absorption on cavity based nonlinear optical switching schemes. We conclude that glass compositions with lower two-photon absorption and more stable properties (reduced photosensitivity) are therefore required for nonlinear applications in chalcogenide photonic crystal cavities.

• 出版日期2010-12-6