Tunable nonlinear optical properties in magnetic nanoparticles suspension under picosecond laser excitation. (October 2021)

• Record Type: Journal Article
• Authors: Yang, Xiangpeng; Li, Decai; Meng, Xiangshen; Li, Qian; Zhang, Huaiwei; Peng, Jiying
• Is Part Of: Optics & laser technology. Volume 142(2021)
• Publication Date: 2021-10
• Subjects: Nanoparticles suspension -- Nonlinear optical absorption -- Nonlinear refraction -- Tunable nonlinear optical properties; Optics -- Periodicals; Lasers -- Periodicals; Electronic journals; 621.366
• DOI: 10.1016/j.optlastec.2021.107260
• Languages: English
• ISSNs: 0030-3992

Abstract

Highlights: Nonlinear optical behaviors of the magnetic colloid were studied by the Z-Scan Technique. Saturation absorption curves of the sample were obtained under laser excitation. The saturation absorption reversed to reverse-saturable absorption as a function of intensity. The nonlinear refraction changed from self-defocusing to self-focusing as a function of intensity. Abstract: In this paper, the intensity-dependent nonlinear optical absorption and nonlinear refraction behaviors of the Fe3 O4 nanoparticles suspension exposed to the 1064 nm picosecond laser pulses (25 ps) were investigated by applying the Z-scan technique. A new type of saturation absorption curve of the magnetic fluids was obtained at lower excitation power levels. As the exciting energy increased, the nonlinear absorption changed from saturable absorption to reverse-saturable absorption, while the nonlinear refraction correspondingly reversed from self-defocusing to self-focusing. These interesting tunable nonlinear optical properties were attributed to the inter-valence charge transfer.