Nonlinear absorption and scattering of a single plasmonic nanostructure characterized by x-scan technique

• Tushar C. Jagadale,
• Dhanya S. Murali and
• Shi-Wei Chu

Beilstein J. Nanotechnol. 2019, 10, 2182–2191, doi:10.3762/bjnano.10.211

• nonlinearity of a single nanostructure, but also reports surprisingly large plasmonic nonlinearities. Keywords: absorption cross section; laser scanning microscopy; nanoplasmonics; nonlinear absorption; nonlinear scattering; single gold nanostructures; Introduction It is well known that the optical

Fe₃O₄ nanoparticles as a saturable absorber for giant chirped pulse generation

• Ji-Shu Liu,
• Xiao-Hui Li,
• Abdul Qyyum,
• Yi-Xuan Guo,
• Tong Chai,
• Hua Xu and
• Jie Jiang

Beilstein J. Nanotechnol. 2019, 10, 1065–1072, doi:10.3762/bjnano.10.107

• . In addition, FONPs also exhibit nonlinear photonic properties such as two-photon absorption, nonlinear scattering, and optical confinement [1][2]. Ferrous ferric oxide (Fe3O4) is a transition metal oxide that has a large third-order nonlinear optical susceptibility of χ(3) = 4.0 × 10−10 esu and an

Nonlinear optical properties of near-infrared region Ag₂S quantum dots pumped by nanosecond laser pulses

• Li-wei Liu,
• Si-yi Hu,
• Yin-ping Dou,
• Tian-hang Liu,
• Jing-quan Lin and
• Yue Wang

Beilstein J. Nanotechnol. 2015, 6, 1781–1787, doi:10.3762/bjnano.6.182

• utilized methods to measure nonlinear behavior. In this study, we used “open-aperture” and “closed-aperture” experiments according to Ganeev et al. [40]. Moreover, to check for the presence of nonlinear scattering, we used a photodiode placed at a fixed angle of about 40°. Insignificant nonlinear

• -scans, which is because of the combination of nonlinear effects in the system [22]. When the laser interacts with the QDs, free-carrier absorption, nonlinear scattering, and saturable absorption will occur, which all contribute to nonlinear behavior. In semiconductor QDs the absorption coefficient and

• scattering of the laser beam was observed. Figure 4 shows the recorded Z-scan graphs of the Ag2S QDs. The laser pump energy ranged from 25 to 45 mJ. We can see that all the open-aperture Z-scan exhibit a transmission maximum at low laser energy, indicating a saturable absorption behavior. However, there is a

Improved optical limiting performance of laser-ablation-generated metal nanoparticles due to silica-microsphere-induced local field enhancement

• Zheren Du,
• Lianwei Chen,
• Tsung-Sheng Kao,
• Mengxue Wu and
• Minghui Hong

Beilstein J. Nanotechnol. 2015, 6, 1199–1204, doi:10.3762/bjnano.6.122

• was believed to be due to nonlinear scattering. Polavarapu et al. [21] have shown that nonlinear absorption was not significant for the gold nanoparticles in water. At low laser fluence, the nanoparticle dispersion is almost transparent to the laser light and thus the laser light exhibits a linear

• , leading to solvent vaporization and bubble formation. These bubbles act as scattering centers, which induces the optical limiting effect [22]. Typically, the contribution from nonlinear scattering becomes dominant at high laser fluence as illustrated in Figure 2b. To verify the optical limiting

• (Au and Ag) exhibited a significant optical limiting effect. The threshold for the optical limiting effect is defined as the laser pulse fluence at which the bubble starts to form, causing significant nonlinear scattering and fluctuation in the output power measurement, which is due to the movement of