Lin, Kung HsuanKung HsuanLinChern, Gia WeiGia WeiChernHuang, Yin ChiehYin ChiehHuangCHI-KUANG SUNKeller, StaciaStaciaKellerMishra, UmeshUmeshMishraDenBaars, Steven P.Steven P.DenBaars2023-08-012023-08-012003-01-011557527490https://scholars.lib.ntu.edu.tw/handle/123456789/634369Huge nonlinear-absorption enhancement was observed in GaN system at the excitonic transition wavelength. This excitonic enhancement is attributed to four-wave-mixing type nonlinear processes. The peak nonlinear coefficient is at least 3000 cm/GW corresponding to an enhancement factor of >200. The dephasing time of the exciton was also observed to be 60-160 fs in GaN thin film at room temperature.conference paper2-s2.0-85135452517https://api.elsevier.com/content/abstract/scopus_id/85135452517