Сверхбыстрая плазмоника и магнитоплазмоника
Surface plasmon-polaritons (SPPs) is a collective oscillation of light and electrons that propagate at the boundary between metal and dielectric. The lifetime of such excitations can vary from few femtoseconds till picoseconds in the optical range of spectrum. Since the development of femtosecond lasers became possible to study and to use this ultrafast processes in devices and applications.
Fig.1 Time-resolved intensity correlation functions measurement setup. Ti:Sa — titanium-sapphire femtosecond laser. Pulse duration — 150 fs, tunable wavelength from 690 nm to 1020 nm, repetition rate of 80MHz, integral power of 1.5-3 V. Step of scanning delay line is 13 fs. BBO — nonlinear crystal. PMT — photomultiplier tube.
Various shaping options (Fig.2), namely, broadening, compression, delaying, advancing, and splitting of the pulses are revealed by spectral tuning of the pulse carrier wavelength in the vicinity of surface plasmon resonances, since such pulse modification strongly depends on the interplay between parameters of the fs-pulse and SPP resonance, for example, laser pulse duration should be comparable with the SPP relaxation time.
Fig.2. Measured correlation functions and reconstructed pulses reflected from the 1D plasmonic crystal for carrier wavelength λ0 in the range from 722 nm to 780 nm.
Fig. 3. Schematics of the ultrafast polarization conversion with plasmonic crystals.