Research on ultraviolet femtosecond pulsed laser cutting 4H-SiC

2020 ◽  
Author(s):  
yunsong huang ◽  
yongdu Li ◽  
yanfei Shen ◽  
qingchun Zhao ◽  
chen Chen ◽  
...  
Keyword(s):  
Laser Cutting ◽  
Pulsed Laser ◽  
Femtosecond Pulsed Laser

Two-photon-excited fluorescence from silicate glass containing tantalum ions pumped by a near-infrared femtosecond pulsed laser

2006 ◽  
Vol 31 (19) ◽  
pp. 2867 ◽  
Author(s):  
Xiangeng Meng ◽  
Katsuhisa Tanaka ◽  
Shunsuke Murai ◽  
Koji Fujita ◽  
Kiyotaka Miura ◽  
...  
Keyword(s):  
Silicate Glass ◽  
Near Infrared ◽  
Pulsed Laser ◽  
Two Photon ◽  
Femtosecond Pulsed Laser

scholarly journals Femtosecond pulsed laser microscopy: a new tool to assess the in vitro delivered dose of carbon nanotubes in cell culture experiments

2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Dominique Lison ◽  
Saloua Ibouraadaten ◽  
Sybille van den Brule ◽  
Milica Todea ◽  
Adriana Vulpoi ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Cell Culture ◽  
Pulsed Laser ◽  
Lung Fibroblasts ◽  
Laser Microscopy ◽  
Cell Responses ◽  
The Impact ◽  
Delivered Dose ◽  
Femtosecond Pulsed Laser

Abstract Background In vitro models are widely used in nanotoxicology. In these assays, a careful documentation of the fraction of nanomaterials that reaches the cells, i.e. the in vitro delivered dose, is a critical element for the interpretation of the data. The in vitro delivered dose can be measured by quantifying the amount of material in contact with the cells, or can be estimated by applying particokinetic models. For carbon nanotubes (CNTs), the determination of the in vitro delivered dose is not evident because their quantification in biological matrices is difficult, and particokinetic models are not adapted to high aspect ratio materials. Here, we applied a rapid and direct approach, based on femtosecond pulsed laser microscopy (FPLM), to assess the in vitro delivered dose of multi-walled CNTs (MWCNTs). Methods and results We incubated mouse lung fibroblasts (MLg) and differentiated human monocytic cells (THP-1) in 96-well plates for 24 h with a set of different MWCNTs. The cytotoxic response to the MWCNTs was evaluated using the WST-1 assay in both cell lines, and the pro-inflammatory response was determined by measuring the release of IL-1β by THP-1 cells. Contrasting cell responses were observed across the MWCNTs. The sedimentation rate of the different MWCNTs was assessed by monitoring turbidity decay with time in cell culture medium. These turbidity measurements revealed some differences among the MWCNT samples which, however, did not parallel the contrasting cell responses. FPLM measurements in cell culture wells revealed that the in vitro delivered MWCNT dose did not parallel sedimentation data, and suggested that cultured cells contributed to set up the delivered dose. The FPLM data allowed, for each MWCNT sample, an adjustment of the measured cytotoxicity and IL-1β responses to the delivered doses. This adjusted in vitro activity led to another toxicity ranking of the MWCNT samples as compared to the unadjusted activities. In macrophages, this adjusted ranking was consistent with existing knowledge on the impact of surface MWCNT functionalization on cytotoxicity, and might better reflect the intrinsic activity of the MWCNT samples. Conclusion The present study further highlights the need to estimate the in vitro delivered dose in cell culture experiments with nanomaterials. The FPLM measurement of the in vitro delivered dose of MWCNTs can enrich experimental results, and may refine our understanding of their interactions with cells.

Measurement of the apex temperature of a nanoscale semiconducting field emitter illuminated by a femtosecond pulsed laser

2018 ◽  
Vol 124 (24) ◽  
pp. 245105
Author(s):  
A. Kumar ◽  
J. Bogdanowicz ◽  
J. Demeulemeester ◽  
J. Bran ◽  
D. Melkonyan ◽  
...  
Keyword(s):  
Pulsed Laser ◽  
Field Emitter ◽  
Femtosecond Pulsed Laser

Femtosecond pulsed laser ablation of thin gold film

2002 ◽  
Vol 34 (3) ◽  
pp. 199-202 ◽  
Author(s):  
K. Venkatakrishnan ◽  
B. Tan ◽  
B.K.A. Ngoi
Keyword(s):  
Laser Ablation ◽  
Gold Film ◽  
Pulsed Laser ◽  
Pulsed Laser Ablation ◽  
Thin Gold Film ◽  
Femtosecond Pulsed Laser

Low-energy femtosecond pulsed laser deposition of cerium (IV) oxide thin films on silicon substrates

2021 ◽  
pp. 126323
Author(s):  
Joseph A. De Mesa ◽  
Angelo P. Rillera ◽  
Melvin John F. Empizo ◽  
Nobuhiko Sarukura ◽  
Roland V. Sarmago ◽  
...  
Keyword(s):  
Thin Films ◽  
Pulsed Laser Deposition ◽  
Pulsed Laser ◽  
Low Energy ◽  
Laser Deposition ◽  
Silicon Substrates ◽  
Oxide Thin Films ◽  
Femtosecond Pulsed Laser

PZT Film and Si Substrate Two-Layer System Patterning Morphology by Femtosecond Pulsed Laser

2007 ◽  
Author(s):  
Shizhou Xiao ◽  
Rui Guo ◽  
Guanghua Cheng ◽  
Yalei Wu ◽  
Wenhao Huang ◽  
...  
Keyword(s):  
Femtosecond Laser ◽  
Laser Energy ◽  
Threshold Model ◽  
Pulsed Laser ◽  
Direct Writing ◽  
Si Substrate ◽  
Layer System ◽  
Substrate Heating ◽  
Pzt Film ◽  
Femtosecond Pulsed Laser

In this paper, a novel PZT film patterning method by femtosecond laser is proposed. The method is different from traditional dry-etching and wet-etching technology. Femtosecond laser microfabrication technology has several advantages such as high resolution, no mask direct-writing and seldom-heating, etc. A two-layer (PZT thin film and substrate) heating and ablating threshold model is built and the relationship of PZT/Si two-layer system micro ablation morphology depending on laser pulse energy is constructed. From the model and experiment data, we obtain the suitable energy region to pattern PZT film freely without damage Si substrate. A 3μm resolution of PZT pattern is achieved in our experiment. In order to verify the fabrication available of this technology, several micro functional devices are successfully patterned by optimized femtosecond pulsed laser energy and their function are detected. The results prove that the PZT patterning quality is good.

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