Dielectric Materials Volume and Surface Processing Using Femtosecond Vortex Beam

We demonstrate the possibility to modify dielectric materials (borosilicate glass) surface and volume using tightly focused femtosecond vortex beams (with different topological charge m = 1; m = 2; m = 3; m = 5; m = 10; m = 25) formed by computer generated amplitude holograms. By controlling femtosecond vortex beam (λ = 1030 nm) waist position Δz, number of incident pulses N, topological charge m and pulse energy EP we get different structures induced: from micron-size ring-shaped to nanosized structures.