Convection roll-driven generation of supra-wavelength periodic surface structures on dielectrics upon irradiation with femtosecond pulsed lasers

Compared with traditional nanotexturing methods, an ultrashort-pulsed laser is an efficient technology of fabricating nanostructures called laser-induced periodic surface structures (LIPSS) on material surfaces. LIPSS are easily fabricated when the pulse duration is shorter than collisional relaxation time (CRT). Accordingly, ultrashort-pulsed lasers have been mainly used to study LIPSS, but they unstably irradiate while requiring high costs. Although long-pulsed lasers have low cost and high stability, the phenomena (such as the effect of pulse duration, laser wavelength, and heat) of the LIPSS fabricated using short-pulsed lasers with the pulse duration close to the maximum CRT, which is greater than femtosecond, have not been clarified. However, the nanosecond pulse laser has been reported to produce LIPSS, but those were unclear and ununiform. In this study, the short-pulsed laser with the pulse duration of 20 ps, which is close to the maximum CRT, was employed to clarify the effects of pulse duration and heat on the fabrication of LIPSS and to solve problems associated with ultrashort-pulsed lasers. First, a finite-difference time-domain simulation was developed at 20-ps pulse duration to investigate the effects of irradiation conditions on the electric-field-intensity distribution. Subsequently, experiments were conducted using the 20-ps pulse laser by varying conditions. The aspect ratio of the LIPSS obtained was greater than that of the LIPSS fabricated using ultrashort-pulsed lasers, but LIPSS were not fabricated at 355- and 266-nm laser wavelength. In addition, the short-pulsed laser experienced thermal influences and a cooling material was effective for the fabrication of LIPSS with high-aspect-ratio. This demonstrates the effects of pulse duration close to the CRT and heat on the fabrication of LIPSS.

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Effect of Crystal Structure on Fabrication of Fine Periodic Surface Structures with Short Pulsed Laser

International Journal of Automation Technology ◽

10.20965/ijat.2018.p0868 ◽

2018 ◽

Vol 12 (6) ◽

pp. 868-875 ◽

Cited By ~ 4

Author(s):

Shuhei Kodama ◽

Shinya Suzuki ◽

Akihiro Shibata ◽

Keita Shimada ◽

Masayoshi Mizutani ◽

...

Keyword(s):

Crystal Structure ◽

Pulse Duration ◽

Pulsed Laser ◽

Surface Structures ◽

Pulsed Lasers ◽

Periodic Surface ◽

Friction Control ◽

Biological Affinity ◽

Ultrashort Pulsed Lasers ◽

Long Pulse

In recent years, nanostructures have been required for industry and medical services, to perform functions such as reduction in friction, control of wettability, and enhancement in biological affinity. Ultrashort pulsed lasers have been applied to meet these demands, and have been actively studied both experimentally and theoretically in terms of phenomena and principles. In this study, to clarify the phenomenon of the fabrication of laser-induced periodic surface structures (LIPSS), and its application to industry, experiments were conducted on SUS304, titanium, and nickel-phosphorus by a short pulsed laser that has a longer pulse duration, higher cost-effectiveness, and higher stability than ultrashort pulsed lasers. The results confirmed that while LIPSS were fabricated on Ti and Ni-P workpieces, a uniform fine periodic structure was not fabricated on the whole irradiated surface of SUS304, and crystal grain boundaries appeared with low energy density and irradiation number because SUS304 is an alloy composed of Fe, Cr, and Ni. Further, the short pulsed laser has a low power and long pulse duration, inducing the thermal effect. We clarified the effect of crystal structure on fabricating fine periodic surface structures with short pulsed laser.

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Formation of laser-induced periodic surface structures on different materials: fundamentals, properties and applications

Advanced Optical Technologies ◽

10.1515/aot-2019-0062 ◽

2020 ◽

Vol 9 (1-2) ◽

pp. 11-39 ◽

Cited By ~ 3

Author(s):

Stephan Gräf

Keyword(s):

Friction And Wear ◽

Review Paper ◽

Laser Wavelength ◽

Single Step ◽

Surface Structures ◽

Direct Writing ◽

Periodic Surface ◽

Experimental Approaches ◽

Ordered Nanostructures ◽

Physical Background

AbstractThe use of ultra-short pulsed lasers enables the fabrication of laser-induced periodic surface structures (LIPSS) on various materials following a single-step, direct-writing technique. These specific, well-ordered nanostructures with periodicities in the order of the utilised laser wavelength facilitate the engineering of surfaces with functional properties. This review paper discusses the physical background of LIPSS formation on substrates with different material properties. Using the examples of structural colours, specific wetting states and the reduction of friction and wear, this work presents experimental approaches that allow to deliberately influence the LIPSS formation process and thus tailor the surface properties. Finally, the review concludes with some future developments and perspectives related to forthcoming applications of LIPSS-based surfaces are discussed.

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Formation of periodic surface structures in multilayer amorphous Ge2Sb2Te5 thin films irradiated by femtosecond laser pulses

Journal of Physics Conference Series ◽

10.1088/1742-6596/1686/1/012006 ◽

2020 ◽

Vol 1686 ◽

pp. 012006

Author(s):

A V Kolchin ◽

D V Shuleiko ◽

S V Zabotnov ◽

L A Golovan ◽

D E Presnov ◽

...

Keyword(s):

Thin Films ◽

Femtosecond Laser ◽

Laser Pulses ◽

Femtosecond Laser Pulses ◽

Surface Structures ◽

Periodic Surface

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Generation of Multiple Vector Optical Bottle Beams

Photonics ◽

10.3390/photonics8060218 ◽

2021 ◽

Vol 8 (6) ◽

pp. 218

Author(s):

Svetlana N. Khonina ◽

Alexey P. Porfirev ◽

Sergey G. Volotovskiy ◽

Andrey V. Ustinov ◽

Sergey A. Fomchenkov ◽

...

Keyword(s):

Intensity Distribution ◽

Polarization State ◽

Spatial Dynamics ◽

Surface Structures ◽

Optical Traps ◽

Spatial Transformation ◽

Optical Elements ◽

Periodic Surface ◽

Matter Interaction ◽

Different Types

We propose binary diffractive optical elements, combining several axicons of different types (axis-symmetrical and spiral), for the generation of a 3D intensity distribution in the form of multiple vector optical ‘bottle’ beams, which can be tailored by a change in the polarization state of the illumination radiation. The spatial dynamics of the obtained intensity distribution with different polarization states (circular and cylindrical of various orders) were investigated in paraxial mode numerically and experimentally. The designed binary axicons were manufactured using the e-beam lithography technique. The proposed combinations of optical elements can be used for the generation of vector optical traps in the field of laser trapping and manipulation, as well as for performing the spatial transformation of the polarization state of laser radiation, which is crucial in the field of laser-matter interaction for the generation of special morphologies of laser-induced periodic surface structures.

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