Lee, Michael WGrillet, ChristianMonat, ChristelleMägi, Eric CTomljenovic-Hanic, SnjezanaGai, XinMadden, SteveBulla, DouglasLuther-Davies, BarryEggleton, Benjamin JChoi, Duk-Yong2015-12-022015-12-021094-4087http://hdl.handle.net/1885/16957We 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 (Ge33As12Se55) 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  63μs  and  93μs  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.This work was produced with the assistance of the Australian Research Council under the ARC Federation Fellowship and Centres of Excellence programs. CUDOS (the Centre for Ultrahigh-bandwidth Devices for Optical Systems) is an ARC Centre of Excellence.8 pages© 2010 Optical Society of Americaphotosensitivechalcogenide glass photonic crystal (PhC)thermo-optic nonlinearphotosensitive refractive index change in AMTIR-1 (Ge33As12Se55)blue-shiftnanocavity resonancethermal bistable2010-12-0610.1364/OE.18.0266952015-12-09