Control of periodic ripples growth on metals by femtosecond laser ellipticity

Abstract

Formation of the periodic ripples on metallic surfaces is investigated comprehensively using variable ellipticities of femtosecond lasers. Compared with the linearly polarized incidence, the well defined grating-like ripple structures rather than the uniform arrays of nanoparticle can always be obtained for the elliptical polarization lasers. The ripple orientation is slanted clockwise or anticlockwise depending on the laser helicity but always display a maximum angle of 45°. Theoretical analyses indicate that no circular polarization is achieved for femtosecond lasers passing through quarter waveplate, and the induced ripple orientation is determined by the major axis of the polarization ellipse. The simulation results agree well with the experimental observations.

Polarization-dependent elliptical crater morphologies formed on a silicon surface by single-shot femtosecond laser ablation

“…The femtosecond (fs) laser, a promising tool for processing a broad range of materials, including metals [1][2][3][4], semiconductors [5][6][7][8][9], and insulators [10][11][12][13], has attracted significant attention due to its wide range of potential applications in many fields, such as colorization [3,6,7], solar cells [5], waveguides [10], surface-enhanced Raman scattering [14,15], microchannels [16,17], and optical data storage [18]. For all of these applications, the forma-tion of well-defined, uniform submicroscale, even nanoscale, structures is a prerequisite.…”

“…Generally, the uniform submicrostructures or nanostructures obtained through the fs laser nanofabrication method closely depend on the irradiation conditions, such as the beam polarization [4,8], the pulse number [12,19], and the laser energy. Recent investigations reveal that laser polarization plays an important role in the formation of laser-induced periodic surface structures (ripples).…”

“…Recent investigations reveal that laser polarization plays an important role in the formation of laser-induced periodic surface structures (ripples). For example, Tang et al studied the influence of variable laser polarizations of incidence on tungsten and copper [4] and found that different regular microstructure orientations could be created with elliptically polarized fs lasers. Very recently, we investigated scanned line width modulation based on polarization changes [8].…”

The spatial emergence of laser-induced periodic surface structures under lateral displacement irradiation conditions

“…Usually, these structures have a unidirectional appearance if produced with linearly p or s polarised light. However, other polarisation states alter their orientation or appearance [122][123][124][125][126]. Because of their generally unidirectional appearance, LIPSS are usually described by their periodicity Λ and orientation Θ.…”

“…Actually this research was triggered by the tissue engineering and implant manufacturing industry, where biodegradable polymers are applied to support the tissue while healing [125]. The success strongly depends on the adhesion and proliferation of the cell-implant contact [174].…”