The efficiency of third harmonic generation (THG) upon noncollinear excitation of a surface plasmon on a metal diffraction grating is studied based on theoretical simulations. The basic channels of the nonlinear interaction of surface plasmons determining the intensity of the THG nonlinear response of the grating are considered. The influence of the period and groove depth of the diffraction grating on the THG efficiency is analysed.
Third-harmonic generation (THG) enhancement caused by the surface-plasmon excitation on a metal diffraction grating is investigated theoretically. Basic features of THG are considered for different ways of the surface plasmon excitation. Nonlinear interactions between the plasmons are analyzed and explained.
Experimental and theoretical investigations of simultaneous surface-enhanced second- and third-harmonic generation on metallic gratings are presented. The good agreement between the model and the experimental data allows us to describe the mutual magnitudes of the surface and bulk contributions to the nonlinear optical response.
The efficiency of excitation of surface plasmons upon noncollinear light scattering from a metal diffraction grating is studied. It is shown that this efficiency strongly depends on the grating profile and the azimuthal angle of rotation. The relation between the spatial configuration of the electromagnetic field near the grating-vacuum interface and the possibility of excitation of plasmons is found. Taking into account different conditions for plasmon excitation, the peculiarities of experimental angular dependences of specular reflection are explained.
It was established that nucleic acids (NA) ofP.pestis possess a specific property of stimulating the immunity in guinea pigs and monkeys in conjoint administration with the live EB vaccine. Conjoint immunization with the live vaccine and NA protected the animals against experimental bubonic (guinea pigs) and pulmonary plague (monkeys). NA ofP.pestis causes no marked immunity in the animals without the live vaccine. Nucleoprotein (NP) and fraction I ofP.pestis, as well as killed microbes of the EB strain, sodium nucleate, and NA ofBr.melitensis, administered together with the live vaccine caused no stimulating effect on the formation of plague immunity in guinea pigs. Fraction I and NA ofP.pestis, as well as sodium nucleate, obtained from yeast in doses and ratios to the live vaccine, depressed the development of immunity to this injection in guinea pigs.
