Ultra-broadband Nonlinear Saturable Absorption for Two-dimensional Bi2TexSe3−x Nanosheets

• Published in: Scientific reports 2016-09, Vol.6 (1), p.33070-33070, Article 33070
• Main Authors: Wang, Yingwei, Liu, Sheng, Yuan, Jian, Wang, Peng, Chen, Jiazhang, Li, Jianbo, Xiao, Si, Bao, Qiaoliang, Gao, Yongli, He, Jun
• Format: Article
• Language: English
• Subjects: 140/125; 639/301/357/1018; 639/624/400/385; Absorption; Humanities and Social Sciences; I.R. radiation; Laboratories; Lasers; Morphology; multidisciplinary; Nitrates; Nonlinear systems; Physics; Receivers & amplifiers; Scanning electron microscopy; Science; Spectrum analysis; Transmission electron microscopy; Wavelength
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/srep33070

We report the ultra-broadband nonlinear optical (NLO) response of Bi 2 Te x Se 3−x nanosheets produced by a facile solvothermal method. Our result show that the extracted basic optical nonlinearity parameters of Bi 2 Te x Se 3−x nanosheets, α NL , Imχ (3) , and FOM reach ~10 4  cm/GW, ~10 −8  esu and ~10 −13  esu cm, respectively, which are several orders of magnitude larger than those of bulk dielectrics. We further observed the excitation intensity dependence of the NLO absorption coefficient and the NLO response sensitivity. The mechanisms of those phenomena were proposed based on physical model. The wavelength dependence of the NLO response of Bi 2 Te x Se 3−x nanosheets was investigated, and we determined that the Bi 2 Te x Se 3−x nanosheets possess an ultra-broadband nonlinear saturable absorption property covering a range from the visible to the near-infrared band, with the NLO absorption insensitive to the excitation wavelength. This work provide fundamental and systematic insight into the NLO response of Bi 2 Te x Se 3−x nanosheets and support their application in photonic devices in the future.