Sub-wavelength ripple formation on various materials induced by tightly focused femtosecond laser radiation

Femtosecond laser induced phenomena in transparent solid materials: Fundamentals and applications

“…The simulation results show that uniform structures, in terms of ablation shapes and subwavelength ripples, can be easily generateded with a lower fluence or subpulse energy ratio of 1:1 with a selected fluence [338]. The incident fluence, angle and wavelength also influence the periodicity [271,285,335,348,349]. More discussions about periodic structures in transparent materials induced by interference fields of femtosecond laser will be given below.…”

“…First, the interference between the incident laser waves and the surface scattered waves can lead to the formation of ripples (LSFLs) with periods close to the wavelengths of radiation lasers [274,276]. Second, the interference between incident light and excited surface plasmons results in generation of sub-wavelength ripples (HSFLs) [261,271,274,276,335]. Furthermore, periodic nanostructures are also fabricated in glass based on the mechanism similar to the second one [19,336].…”

Manufacturing of Nd:Gd3Ga5O12 ridge waveguide lasers by pulsed laser deposition and ultrafast laser micromachining

“…For the fabrication of the ridge waveguides, grooves are structured by ablation with femtosecond laser radiation using a 63Â microscope objective with NA 0.7 (Thales laser concerto) or a 50Â microscope objective with NA 0.55 (IMRA mJewel). The polarization of the laser radiation is perpendicular to the scanning direction to prevent rough edges due to ripple formation perpendicular to the waveguides edge [12,13]. Using three parallel scans with 350 nm, offset (approximation scanning [10]) results in a 1 mm deep and 1 mm wide groove with a smooth edge in the deposited films.…”

Genesis of femtosecond-induced nanostructures on solid surfaces

“…The regular, periodic modification of solid-surface morphology by irradiation with ultra-short (sub-picosecond) laser pulses, laser-induced periodic surface structures (LIPSS or ripples) has found increased attraction in recent years [1][2][3][4][5][6][7][8][9][10][11][12]. (For a review see [13].)…”