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

• communication. Here, we report the use of FONPs synthesized by a sol–hydrothermal method and used as a saturable absorber (SA) to achieve nanosecond pulses in an erbium-doped fiber laser (EDFL) for the first time. The proposed fiber laser is demonstrated to have a narrow spectral width of around 0.8 nm and a

Oriented zinc oxide nanorods: A novel saturable absorber for lasers in the near-infrared

• Pavel Loiko,
• Tanujjal Bora,
• Josep Maria Serres,
• Haohai Yu,
• Magdalena Aguiló,
• Francesc Díaz,
• Uwe Griebner,
• Valentin Petrov,
• Xavier Mateos and
• Joydeep Dutta

Beilstein J. Nanotechnol. 2018, 9, 2730–2740, doi:10.3762/bjnano.9.255

• ZnO NRs are applied as saturable absorbers in diode-pumped Yb (≈1.03 µm) and Tm (≈1.94 µm) lasers generating nanosecond pulses. The ZnO NRs grown on various optical surfaces are promising broadband saturable absorbers for nanosecond near-IR lasers in bulk and waveguide geometries. Keywords: oriented

• , e.g., MoS2, WS2 [16][17], black phosphorus (BP) [18]), and topological insulators (TIs, e.g., Bi2Te3, Sb2Te3 [19][20], graphitic carbon nitride (g-C3N4) [21]). In the PQS regime, such structures enable the generation of nanosecond pulses at high repetition rates (up to MHz) and they are attractive for

• 1.039 µm [42]. Thus, the present work, for the first time, demonstrates the ability of ZnO nanostructures to generate nanosecond pulses. Conclusion Hydrothermally grown hexagonal-shaped [001]-oriented ZnO NRs are a promising material for broadband saturable absorbers for near-IR lasers (1–2 µm). In the

Laser-assisted fabrication of gold nanoparticle-composed structures embedded in borosilicate glass

• Nikolay Nedyalkov,
• Mihaela Koleva,
• Nadya Stankova,
• Rosen Nikov,
• Mitsuhiro Terakawa,
• Yasutaka Nakajima,
• Lyubomir Aleksandrov and
• Reni Iordanova

Beilstein J. Nanotechnol. 2017, 8, 2454–2463, doi:10.3762/bjnano.8.244

• nanoparticle formation was observed in the samples irradiated by nanosecond pulses at 355, 532 and 1064 nm. The optical properties of the irradiated areas were found to depend on the laser processing parameters; these properties were studied based on Mie theory, which was also used to correlate the

• increases the absorbance. As in the case of irradiation using nanosecond pulses at 266 nm, two bands with similar characteristics can be identified. Thus, one can conclude that femtosecond radiation induces the same type of defects in the glass matrix. The samples irradiated by femtosecond pulses were

• propagation and absorption mechanisms, whose detailed description is yet to be performed. The similar behavior exhibited by the glass samples after irradiation by 266 nm nanosecond pulses hints at the same kinetics of nanoparticle formation. An estimate of the particle size, based on the plasmon band position

Laser processing of thin-film multilayer structures: comparison between a 3D thermal model and experimental results

• Babak B. Naghshine and
• Amirkianoosh Kiani

Beilstein J. Nanotechnol. 2017, 8, 1749–1759, doi:10.3762/bjnano.8.176

• ; nanosecond pulses; silicon; thin-film; Introduction Laser processing of thin-film multilayer structures has been studied since the early 1990s [1]. However, the field has been largely neglected by researchers and there have been very few studies in this area [2][3][4]. On the other hand, it has many

• see the profile of the holes generated by the laser beam on the surface of the samples. Numerical model Heat transfer model Since nanosecond pulses (where the pulse duration is in the nanosecond range) are studied in this paper, the whole process is in the hot-ablation domain. Therefore, the process

The role of morphology and coupling of gold nanoparticles in optical breakdown during picosecond pulse exposures

• Yevgeniy R. Davletshin and
• J. Carl Kumaradas

Beilstein J. Nanotechnol. 2016, 7, 869–880, doi:10.3762/bjnano.7.79

• [34][35]. For nanosecond pulses [28] or ultrashort pulse sequences separated by times of the order of the free-electron energy thermalization time [36], LITB is a significant source of seed electrons, ρseed, which is required to initiate the avalanche ionization [28], when the temperature of the

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

• surrounding the QDs will be changed. Ag2S has a narrow band gap, which leads to the strong absorption characteristics of Ag2S and which makes Ag2S particularly suitable for use in optical detectors and solar cells. Conclusion In summary, we have demonstrated, using NIR Ag2S QDs pumped by 532 nm nanosecond

• pulses, that the nonlinear optical characteristics can be efficiently generated in QDs. The simulation results show the nonlinear characteristics of Ag2S QDs. Nonlinear transmission measurement revealed that Ag2S QDs have a superior nonlinear optical performance because of their strong absorption

Photodetectors based on carbon nanotubes deposited by using a spray technique on semi-insulating gallium arsenide

• Domenico Melisi,
• Maria Angela Nitti,
• Marco Valentini,
• Antonio Valentini,
• Teresa Ligonzo,
• Giuseppe De Pascali and
• Marianna Ambrico

Beilstein J. Nanotechnol. 2014, 5, 1999–2006, doi:10.3762/bjnano.5.208

• ; spray technique; UV–NIR; Introduction Fast photoconductive detectors (PCD) are widely used for the characterization of sub-nanosecond pulses generated from infrared (IR) to ultraviolet (UV) light, X-ray and gamma-ray photons, as well as charged particles [1][2][3]. Applications of carbon nanotubes

Current state of laser synthesis of metal and alloy nanoparticles as ligand-free reference materials for nano-toxicological assays

• Christoph Rehbock,
• Jurij Jakobi,
• Lisa Gamrad,
• Selina van der Meer,
• Daniela Tiedemann,
• Ulrike Taylor,
• Wilfried Kues,
• Detlef Rath and
• Stephan Barcikowski

Beilstein J. Nanotechnol. 2014, 5, 1523–1541, doi:10.3762/bjnano.5.165

• polydispersity of the samples is generally larger when picosecond instead of nanosecond pulses are used during the ablation process. During PLAL a laser pulse hits the target and generates a plasma plume, whose onset is reported to occur tens of picoseconds after pulse absorption and contains a variety of

• plume while in the case of nanosecond pulses the plasma plume may absorb further energy from the laser pulse, which may be responsible for homogenization of the ejected material [24][48][49] and hence more narrow size distributions. In the case of femtosecond laser ablation, particularly at high laser

• -free environments, where the application of nanosecond pulses at λ = 532 nm enables control of the particle diameters in a range from 4–30 nm for a variation of the laser fluence from 12–442 mJ/cm2 (Figure 2B). Furthermore, it was shown that PLFL may be influenced by the ambient pressure, though these

Mapping of plasmonic resonances in nanotriangles

• Simon Dickreuter,
• Julia Gleixner,
• Andreas Kolloch,
• Johannes Boneberg,
• Elke Scheer and
• Paul Leiderer

Beilstein J. Nanotechnol. 2013, 4, 588–602, doi:10.3762/bjnano.4.66

• diffusion times. When using pico- and nanosecond pulses instead, the heat diffusion results in controlled melting of the nanostructures. The findings will be compared to the results of FDTD simulations, and also the limitations of the two techniques will be discussed. Finally we discuss the field-enhancing

• process of these molten structures is different, however, from the removal of (nearly intact) triangles by fs pulses. It has been described for the case of nanosecond pulses by Habenicht et al. [37]. Basically, the potential energy that is stored in a flat triangle as compared to the round droplet form on