A method of obtaining a periodic structure on a surface of a substrate , using a pulsed laser beam having a wavelength λ, wherein the method comprises the steps of: - providing the substrate being made of material having an imaginary part of dielectric permittivity equal or higher than the absolute value of its real part for the laser beam wavelength λ; and - irradiating a spot on the surface of the substrate by the pulsed laser beam , wherein - the laser pulse duration of said laser beam is less than the time required by electrons in the substrate for thermalization with a lattice; and - the pulsed laser beam is linearly polarized to induce surface electromagnetic waves propagating on said surface along the polarization direction; and - < the diameter of the irradiated spot on the substrates surface is smaller than three characteristic decay lengths of said surface electromagnetic wave and wherein the diameter of the irradiated spot is less or equal than 30 μm; and > - fluence of the pulsed laser beam is higher than the ablation threshold, - irradiation of the surface of the substrate is performed by irradiation of a plurality spots, wherein the spots partially overlap each other, wherein the overlap between two pulses is at least 30%, characterized in that < -> in that said periodic structure has a dispersion angle of FFT signal less than 15°. - providing the substrate being made of material having an imaginary part of dielectric permittivity equal or higher than the absolute value of its real part for the laser beam wavelength λ; and - irradiating a spot on the surface of the substrate by the pulsed laser beam , wherein - the laser pulse duration of said laser beam is less than the time required by electrons in the substrate for thermalization with a lattice; and - the pulsed laser beam is linearly polarized to induce surface electromagnetic waves propagating on said surface along the polarization direction; and - < the diameter of the irradiated spot on the substrates surface is smaller than three characteristic decay lengths of said surface electromagnetic wave and wherein the diameter of the irradiated spot is less or equal than 30 μm; and > - fluence of the pulsed laser beam is higher than the ablation threshold, - irradiation of the surface of the substrate is performed by irradiation of a plurality spots, wherein the spots partially overlap each other, wherein the overlap between two pulses is at least 30%, characterized in that < -> in that said periodic structure has a dispersion angle of FFT signal less than 15°. - the laser pulse duration of said laser beam is less than the time required by electrons in the substrate for thermalization with a lattice; and - the pulsed laser beam is linearly polarized to induce surface electromagnetic waves propagating on said surface along the polarization direction; and - < the diameter of the irradiated spot on the substrates surface is smaller than three characteristic decay lengths of said surface electromagnetic wave and wherein the diameter of the irradiated spot is less or equal than 30 μm; and > - fluence of the pulsed laser beam is higher than the ablation threshold, - irradiation of the surface of the substrate is performed by irradiation of a plurality spots, wherein the spots partially overlap each other, wherein the overlap between two pulses is at least 30%, characterized in that < -> in that said periodic structure has a dispersion angle of FFT signal less than 15°. <EOS>