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An investigation was made of the visible radiation emitted by planar metal–barrier–metal structures as a result of decay of plasma oscillations. A method was found for increasing the intensity of the output radiation using a barrier in the form of a multilayer insulator consisting of different oxides evaporated consecutively. It was found experimentally that the efficiency of emission by these structures was twice that of structures with a simple barrier. The rise time of an optical response of such metal–barrier–metal structures to a single short voltage pulse was at least 4 nsec. The output radiation intensity increased under the additional action of a microwave field of frequency up to 1.2 GHz. This property could be used for the purpose of fast-response visualization of microwave fields with a sensitivity threshold of ~1 mW/cm2.

Theoretical and experimental investigations were made of the scattering of surface electromagnetic waves at an interface between a metal and a liquid crystal in metal–insulator–metal–liquid crystal structures. Surface electromagnetic waves were created as a result of electron tunneling in the metal–insulator–metal part of a structure and these waves were scattered by a periodic inhomogeneity of the permittivity of the liquid crystal.

An investigation was made of the angular distribution of the luminescence emitted by a metal–barrier–metal (MBM) diode formed on a smooth substrate. The brightness of the p-polarized luminescence observed at an angle of 80° relative to the normal to the diode plane was 65 times higher than the intensity along the normal, whereas the s-polarized luminescence was 16 times greater. Calculations indicated that in the case of an MBM diode formed on a smooth substrate such an angular distribution in the case of the p-polarized component of the luminescence originating from decay of surface plasma oscillations at the insulator–metal interface may be governed not only by the interaction of plasmons with inhomogeneities of certain size of the metal (silver) film, but can also be influenced by the ratio of the permittivities of the media.

A study was made of light emitted as a result of decay of surface plasma oscillations in metal–oxide–metal structures. An absolute increase in the intensity of this light and its control were achieved by using a medium external to the metal film. This medium was a liquid crystal forming a domain structure in a static electric field. The arrangement provided a convenient means for investigating the processes of radiative decay of surface plasmons.

An increase in the efficiency of light emission (by over an order of magnitude) was achieved for plasma oscillations in a thin silver film of a gold–aluminum oxide–silver (Au–Al2O3–Ag) structure by altering the permittivity of a nematic liquid crystal adjoining the silver film.

An experimental study was made of the amplification of surface plasma oscillations due to a negative differential resistance of an Au–Al2O3–In2O3–Al2O3–In2O3–Al2O3–Ag structure resulting from resonance tunneling of electrons in a periodic potential field of a complex insulator barrier in this metal–barrier–metal structure.

A study was made of the influence of the technology used in the fabrication of a dielectric barrier on the luminescence spectrum of a metal–barrier–metal (MBM) diode. The barrier was formed by electron-beam sputtering or by ion implantation. Various methods of fabrication of the barrier layer affected the electrophysical characteristics, but not the spectral properties of tunnel MBM diodes. This confirmed that the plasma mechanism was the main reason for the luminescence of radiation by MBM diodes.

The luminescence of a planar tunnel metal/barrier/metal (MBM) structure with a 40-A-thick Al2O3 dielectric layer under the action of short-pulse voltage and hf electromagnetic emission is investigated. The optical response is greater than 10 -3 W of light per watt of hf signal in the measurement range of 500 to 1200 MHz. The MBM structure can be used as a fast-operating visualizer of hf signals.