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Laser-Induced Formation of Periodic Structures on the Metal Surfaces and Surface Plasmons Excitation

Quasiperiodic microstructures are formed on the surfaces of metals under irradiation with high-power femtosecond laser pulses. Interpretation of microstructures as a result of interference of the incident plane wave and surface waves leads to the logical conclusion about the relationship of dislocations in the interference fringes with optical vortices in surface wave. Other peculiarities observed in these structures contain different periods and nanogranular fine structure. It is demonstrated that such laser-induced structures can find applications for surface plasmon excitation and surface enhanced Raman scattering.