Unique Functional Micro/nano-structures Created by Femtosecond Laser Irradiation

2003 ◽  
Vol 780 ◽  
Author(s):  
M.H. Hong ◽  
S.M. Huang ◽  
W.J. Wang ◽  
K.S. Tiaw ◽  
S.H. Teoh ◽  
...  
Keyword(s):  
Laser Irradiation ◽  
Data Storage ◽  
Near Field ◽  
Three Dimensional ◽  
Chemical Properties ◽  
Optical Recording ◽  
Femtosecond Laser Irradiation ◽  
Laser Applications ◽  
Fs Laser ◽  
Hole Arrays

AbstractFemtosecond (fs) laser application in three-dimensional (3D) optical recording is introduced. The laser irradiation on transparent glass and polymer matrix doped with fluorescent material is carried out, which changes the physical or chemical properties of the recording media and records information bits. With the change of the focusing positions inside the transparent substrates, 3D optical recording can be available for ultrahigh capacity data storage. Feasibility on fs laser drilling of poly-caprolactone (PCL) thin films for tissue engineering is investigated. It is found that precisely defined micro-hole arrays can be formed on the sample surfaces. Hydrophilic property of the processed samples is much improved, which provides good conditions for tissue cells to anchor on the man-made skin. Fs laser applications to form nanostructures on substrate surfaces are studied. Fs laser combination with near-field scanning optical microscopy (NSOM) to induce surface property modification in the sub 50-nm under NSOM tip and nanoparticles is also discussed.

scholarly journals Role of the La/K Compositional Ratio in the Properties of Waveguides Written by Fs-Laser Induced Element Redistribution in Phosphate-Based Glasses

Materials ◽  
2020 ◽  
Vol 13 (6) ◽  
pp. 1275 ◽  
Author(s):  
Pedro Moreno-Zarate ◽  
Francisco Muñoz ◽  
Belen Sotillo ◽  
Manuel Macias-Montero ◽  
Julia Atienzar ◽  
...  
Keyword(s):  
Refractive Index ◽  
Glass Composition ◽  
Near Field ◽  
Phosphate Glasses ◽  
Femtosecond Laser Irradiation ◽  
Local Modification ◽  
Fs Laser ◽  
Index Contrast ◽  
Element Redistribution ◽  
Local Enrichment

The local modification of the composition of glasses by high repetition femtosecond laser irradiation is an attractive method for producing photonic devices. Recently, the successful production of waveguides with a refractive index contrast (Δn) above 10−2 by fs-laser writing has been demonstrated in phosphate glasses containing La2O3 and K2O modifiers. This large index contrast has been related to a local enrichment in lanthanum in the light guiding region accompanied by a depletion in potassium. In this work, we have studied the influence of the initial glass composition on the performance of waveguides that are produced by fs-laser induced element redistribution (FLIER) in phosphate-based samples with different La and K concentrations. We have analyzed the contribution to the electronic polarizability of the different glass constituents based on refractive index measurements of the untreated samples, and used it to estimate the expected index contrast caused by the experimentally measured local compositional changes in laser written guiding structures. These estimated values have been compared to experimental ones that are derived from near field images of the guided modes with an excellent agreement. Therefore, we have developed a method to estimate before-hand the expected index contrast in fs-laser written waveguides via FLIER for a given glass composition. The obtained results stress the importance of considering the contribution to the polarizability of all the moving species when computing the expected refractive index changes that are caused by FLIER processes.

scholarly journals Synthesis of bio-functionalized three-dimensional titania nanofibrous 3 using femtosecond laser ablation

2021 ◽  
Author(s):  
Amirhossein Tavangar ◽  
Bo Tan ◽  
Krishnan Venkatakrishnan
Keyword(s):  
Femtosecond Laser ◽  
Three Dimensional ◽  
Titanium Substrate ◽  
Chemical Properties ◽  
Femtosecond Laser Ablation ◽  
Cell Interaction ◽  
Primary Objective ◽  
Femtosecond Laser Irradiation ◽  
Ambient Conditions

The primary objective of current tissue regeneration research is to synthesize nano-based platforms that 24 can induce guided, controlled, and rapid healing. Titanium nanotubes have been extensively considered 25 as a new biomaterial for biosensors, implants, cell growth, tissue engineering, and drug delivery systems. 26 However, cell adhesion to nanotubes is poor due to their chemical inertness, as well as the one-dimen- 27 sional structure, and surface modification is required to enhance nanotube–cell interaction. While there 28 have been a considerable number of studies on growing titanium nanotubes, synthesizing a three-dimen- 29 sional (3-D) nano-architecture which can act as a growth support platform for bone and stem cells has 30 not been reported so far. Therefore, we present a novel technique to synthesize and grow 3-D titania 31 interwoven nanofibrous structures on a titanium substrate using femtosecond laser irradiation under 32 ambient conditions. This surface architecture incorporate the functions of 3-D nano-scaled topography 33 and modified chemical properties to improve osseointegration while at the same time leaving space to 34 deliver other functional agents. The results indicate that laser pulse repetition can control the density 35 and pore size of engineered nanofibrous structures. In vitro experiments reveal that the titania nanofi- 36 brous architecture possesses excellent bioactivity and can induce rapid, uniform, and controllable 37 bone-like apatite precipitation once immersed in simulated body fluid (SBF). This approach to synthesiz- 38 ing 3-D titania nanofibrous structures suggests considerable promise for the promotion of Ti interfacial 39 properties to develop new functional biomaterials for various biomedical applications.

scholarly journals Experimental Investigation Of Nanostructures Generated On Glasses Using A MHz Femtosecond Laser

2021 ◽  
Author(s):  
Dheeraj Vipparty
Keyword(s):  
Femtosecond Laser ◽  
Laser Irradiation ◽  
Dwell Time ◽  
Three Dimensional ◽  
Soda Lime ◽  
Femtosecond Laser Irradiation ◽  
Soda Lime Glass ◽  
Ambient Conditions ◽  
Nanoparticle Agglomerate ◽  
Insight Into

This dissertation reports the synthesis of unique Si0₂ based nanostructures by exposing glass samples to MHz repletion rate femtosecond laser irradiation. A three-dimensional fibrous nanoparticle agglomerate network was observed on soda-lime glass (73% SiO + other compounds) when exposed to femtosecond laser irradiation at 8.4 MHz and 12.6 MHz repetition rate and 0.5 ms dwell time, in air. By irradiating silica glass (96% SiO₂+ trace elements) sample under ambient conditions with femtosecond pulses at 12.6 MHz and dwell time in excess of 3.0 ms; long continuous nanofibers of extremely high aspect ration (certain fibers up to 100000:1) were obtained. The mechanisms that promote such nanostructures with distinct morphologies have been explored. A deeper insight into the fundamentals of femtosecond laser interaction with dielectrics led to the understanding that variations in bandgap alters ablation dynamics and dictates the response of glass to femtosecond laser irradiation, ultimately resulting in the formation of structures with dissimilar morphology on silica and soda-lime glass.

scholarly journals Experimental Investigation Of Nanostructures Generated On Glasses Using A MHz Femtosecond Laser

2021 ◽  
Author(s):  
Dheeraj Vipparty
Keyword(s):  
Femtosecond Laser ◽  
Laser Irradiation ◽  
Dwell Time ◽  
Three Dimensional ◽  
Soda Lime ◽  
Femtosecond Laser Irradiation ◽  
Soda Lime Glass ◽  
Ambient Conditions ◽  
Nanoparticle Agglomerate ◽  
Insight Into

This dissertation reports the synthesis of unique Si0₂ based nanostructures by exposing glass samples to MHz repletion rate femtosecond laser irradiation. A three-dimensional fibrous nanoparticle agglomerate network was observed on soda-lime glass (73% SiO + other compounds) when exposed to femtosecond laser irradiation at 8.4 MHz and 12.6 MHz repetition rate and 0.5 ms dwell time, in air. By irradiating silica glass (96% SiO₂+ trace elements) sample under ambient conditions with femtosecond pulses at 12.6 MHz and dwell time in excess of 3.0 ms; long continuous nanofibers of extremely high aspect ration (certain fibers up to 100000:1) were obtained. The mechanisms that promote such nanostructures with distinct morphologies have been explored. A deeper insight into the fundamentals of femtosecond laser interaction with dielectrics led to the understanding that variations in bandgap alters ablation dynamics and dictates the response of glass to femtosecond laser irradiation, ultimately resulting in the formation of structures with dissimilar morphology on silica and soda-lime glass.

Synthesis of Nanocrystalline Hexagonal Diamond Films in Organic Solvents by Femtosecond Laser Irradiation

2007 ◽  
Vol 1039 ◽  
Author(s):  
Anming Hu ◽  
Walt W. Duley
Keyword(s):  
Laser Irradiation ◽  
Organic Solvents ◽  
Diamond Films ◽  
Photoelectron Spectra ◽  
Femtosecond Laser Irradiation ◽  
Metal Catalyst ◽  
Ion Chemistry ◽  
Hexagonal Diamond ◽  
Fs Laser ◽  
Average Size

AbstractNanocrystalline diamond films have been synthesized on various substrates by 800 nm fs laser irradiation of a variety of organic solvents including acetone, pentane, hexane, heptane, octane, dodecane, and hexadecane in the presence of a transition metal catalyst. 632 nm Raman spectra display a strong vibration mode at 1308 cm−1 characteristic of hexagonal diamond. X-ray photoelectron spectra confirm that the film is mainly sp3-bonded carbon containing a low concentration of sp2-bonded inclusions. Film microstructure shows that these films are assembled from nanoparticles having an average size of < 100 nm. Analysis of the liquid after irradiation using HPLC techniques indicates that polyyne molecules are also synthesized during irradiation. It is possible that these species are formed as the products of ion chemistry following Coulomb explosion. This process may enable a new method for the creation of nanocrystalline hexagonal diamond layers for micro-electronic and other applications.

Sign in / Sign up

Export Citation Format

Share Document