In the following thesis to operation a new principle of Si application is offered as a emitter on mid and long infrared (IR) spectral range, which is based on the modulation of a thermal emission (TE) power of the semiconductor in a spectral range of intraband electronic transitions at excitation by emission with quantum energy, that exceeds energy band-gap of the semiconductor. The investigation of radiation influence mechanism from the field of Si fundamental absorption on its below band-gap thermal emission in a wide temperature range (300 - 800 К) is carried out. It is shown, that its power depends on free charge carriers concentration. The concentration change was carried out by optical light injection from the fundamental absorption range; this process was regarded as transformation of short-wave radiation into long-wave (light down conversion). The efficiency dependences of such transformation on parameters of exterior actions (temperature semiconductor, intensity and wavelength of stimulating light) and parameters of Si crystals (material, concentration and type of impurities, lifetime of charge carriers, a surface conditions, thickness) are obtained. The parameters of the material and samples, optimal for reaching maximal efficiency of a short-wave light transformation into a long-wave one, are determined. The temperature range, in which maximum values of Si-emitters power are achieved, is explored; their limiting values in isothermal condition are set. The influence of single-layer antireflection coating on integral and spectral distribution of power of such emitters is explored. It is shown, that as a result of such coating, the maximum power of non-equilibrium ТE in spectral ranges 3-5 and 8-12 microns will increase almost up to ТE power of black body and a re-structuring of a spectrum takes place. The methods of Si-emitters performance increase by the diminution of a surface recombination velocity (by a pulsing laser deposition of films with silicon quantum dots), selection of a wave length ofpumping light and temperature, use of antireflection coating are offered. By the results of the investigation the following issues were offered: a photonic Si-emitter with optical control, capable to simulate as "hot" (Т> > 0 0C), and "cold" (Т << 0 0C) objects in IR spectral range (3-12 microns), that does not require actual cooling of the emitter itself and works at high temperatures; a new type of a photon multispectral emitter with controllable parameters, capable to simulate objects with different thermal contrast in spectral ranges 3-5 and 8-12 m; photonic IR emitter of the large area (some square centimeters), the emission spectrum of which is not affected the semiconductor energy band-gap, that combines advantages of both light-emitting diode (the opportunity to generate emission both positive, and negative contrasts, high speed action), and thermal emitter (wide spectral range, high operating temperatures); The impulse extender (which operation bases on the saturation effect of the semiconductor emissivity at a high level of photo-excitation); non-contact, high-temperature, non-destructive, all-optical methods of measuring of semiconductors recombination parameters (diffusion length, lifetime and surface recombination velocity). Their advantages over existing analogs are proved. Key words: silicon, thermal emission, edge of fundamental absorption, absorption by free carriers, 3-5 and 8-12 m infrared ranges, velocity of a surface recombination, diffusion length, lifetime of charge carriers.
