Results

Graphics

Comparing laser patterning

Laser4Surf All-in-one machine

Bone cells develop better on a nano structured surface.

Roll-up banner

Roll-up poster providing the key facts and outputs of Laser4Surf project.

Roll-up banner (medical components)

Roll-up poster providing the key facts and outputs for the application “Medical Components” of Laser4Surf project.

Brochure

Public deliverables

The present deliverable is “Public” in nature, i.e. it is not a report. For convenience, we provide a short report about the structure and features of the LASER4SURF website and the LASER4SURF social media channels on LinkedIn and Twitter.

The project is expected to produce an introductory project video within the first four months of the project. The LASER4SURF introductory video is intended as a general presentation tool to be shown on the LASER4SURF website, at fairs, conferences or other relevant events and upon request. Targets for distribution are researchers and stakeholders at large. The LASER4SURF introductory video is aimed at informing relevant stakeholder communities of the general purpose of the project, its objectives, technologies used, targets and expected impacts deliverable.

This deliverable contains the project brochure, that will operate as a tool to present the project and to support project communication at workshops, fairs and conferences.

Scientific publications

Femtosecond laser fabrication of LIPSS-based waveplates on metallic surfaces

To read full paper, please click on image to the left.

Tailored femtosecond laser fabrication of reflective waveplates

San-Blas, Alejandro; Casquero, Noemi; Martinez-Calderon, Miguel; Buencuerpo, Jeronimo; Sanchez-Brea, Luis Miguel; del-Hoyo, J; Olaizola, Santiago Miguel; Rodriguez, Ainara; Gomez-Aranzadi, Mikel

Laser induced periodic surface structures (LIPSS) can be studied as waveplates due to the birefringence induced by the nanoripples, with easy fabrication since they are fabricated in a one-step process by laser, where LIPSS geometry are defined by the characteristics of the laser and the substrate. The optical properties of these waveplates are defined by LIPSS parameters such as period, depth or width of the ripples. In this work we have measured the change in polarization of the light reflected from LIPSS generated on stainless steel. Results show a gradual change in polarization as the parameters employed in the fabrication vary. As shown in our experiments with a setup based in cylindrical focusing lens, the fast fabrication of samples with applications as waveplates is demonstrated.

Proceedings of LiM 2019

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Innovative method to enhance the control over the fabrication of LIPSS on metallic surfaces

Gomez-Aranzadi, Mikel; Casquero, Noemi; Martinez-Caldero, Miguel; San-Blas, Alejandro; Olaizola, Santiago Miguel; Rodriguez, Ainara

LIPSS are an emergent method of fabricating functional surfaces. A high repetition rate ultrashort pulsed laser was used to generate LIPSS on metallic surfaces. Different combinations of the processing parameters were tested to study their effect on the period of the LIPSS. Additionally, the influence of the repetition rate (laser frequency) on the LIPSS period was also studied when the same number of pulses, polarization and peak fluences are applied. Finally, a chemical analysis was performed in order to establish a correlation between the laser processing conditions and the resulting chemical modifications (especially oxidation) in the ultrashort pulse regime. As expected, the analysis shows a decrease in the period of the LIPSS as the number of pulses increases, while the other processing parameters affect the period slightly. Regarding the laser frequency, variations in the repetition rate –while the rest of the parameters are kept constant- only slightly affect the period and morphology of the LIPSS.  In the case of the chemical variations, two different regimes were found, with Low Spatial Frequency LIPSS exhibiting no oxidation for low accumulated fluences and High Spatial Frequency LIPSS presenting increased oxidation as the fluences accumulate.

Proceedings of Lasers in Manufacturing 2019

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Fabrication of LIPSS-based metallic polarization gratings

San Blas, Alejandro; Rodriguez, Ainara; Casquero, Noemi; Olaizola, Santiago Miguel; Martinez-Calderon, Miguel; Gomez-Aranzadi, Mikel

Birefringence induced by nanoripples generated by laser (Laser Induced Periodic Surface Structures, LIPSS), enables their use as polarization gratings. Their fabrication is simple, as LIPSS ge­ometry is defined by the characteristics of the laser and the substrate in a one-step process. In this work LIPPS generated on stainless steel have been used to measure the change in polarization of the light reflected on them. Parameters such as period, depth or width of the ripples define the optical properties of these polarization gratings. As the fabrication parameters change, results show a grad­ual change in polarization. Our experiments, performed with a setup based in cylindrical focusing lens, demonstrate the fast fabrication of samples for different applications, such as waveplates.

Proceedings of LAMP 2019

To read full paper, please click on image to the left.

Polarization conversion on nanostructured metallic surfaces fabricated by LIPSS

Casquero, Noemi; Martinez-Calderon, Miguel; Perez, Noemi; Granados, Eduardo; Olaizola, Santiago M.; Rodriguez, Ainara

Fabricating reflective waveplates using nanostructured surfaces has taken great interest in recent years due to their simple structure: a diffractive grating composed of ripples with subwavelength period. The surface ripples act as an artificial birefringent material: the anisotropy of the surface corrugation generates a phase delay between two perpendicular light polarizations. The control of the period, fill factor, depth and orientation of the ripples are crucial to optimize the change of the polarization of the reflected light. Although there are different strategies to fabricate subwavelength diffraction gratings to convert the polarization of light in reflection mode, here we propose the use of Laser Induced Periodic Surface Structures (LIPSS) as a new approach for this purpose. In this work, large area subwavelength reflective gratings have been fabricated via LIPSS with periods of 580 nm and 630 nm. These gratings were able to convert the incident linear polarized laser light at 633 nm into reflected circular polarized light, and vice versa, with ellipticity values lower than 2,7°. This is, to the best of our knowledge, the first report on the use of LIPSS for polarization conversion.

Conference proceeding of the work presented in LPM2018

To read full paper, please click on image to the left.

Tailoring birefringence of LIPSS through thin film coatings

San Blas, Alejandro; Casquero, Noemi; Sanchez, Sergio; Sanchez-Brea, Luis Miguel; Buencuerpo, Jerónimo; Rodriguez, Ainara; Olaizola, Santiago M.

Waveplates modify polarization by generating a phase change. Laser Induced Periodic Surface Structures (LIPSS) have recently started to be studied as waveplates due to the birefringence induced by the nanoripples, easily fabricated in a one-step process by laser, where LIPSS morphology is defined by the characteristics of the laser process parameters and the substrate material. The optical properties of these waveplates are defined by LIPSS parameters such as period, depth or width of the ripples. In this work we have deposited thin film coatings on stainless steel samples containing LIPSS for different coating thickness and composition. Results show that thin film coatings are a good candidate for the tunability of LIPSS birefringence since the coating modifies the induced polarization change and reflectivity of the sample depending on coating thickness and composition, as expected from numerical simulations.

Conference proceeding of the work presented in LPM 2018

To read full paper, please click on image to the left.