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50 OPTOINFORMATICS’05 LIGHT EMISSION BY THE NANOMETER-SCALE STRUCTURES T.A.Kudykina, A.I.Pervak University “Ukraina”, Department <strong>of</strong> Engineering Technologies, vul. Horiva, 1 Γ , Kiev-71, Ukraine, 04071 E-mail: tkudykina@ukr.net It is shown that the nanometer-scale structures (quantum wells, dots, porous silicon, thin films) are the oscillatory systems with the natural frequencies in the spectral region from ultraviolet to infrared. The visible luminescence <strong>of</strong> the nanometer-scale objects and the radiowave generation by an oscillatory circuit are the similar processes but in the different regions <strong>of</strong> 1 frequencies. The natural frequency <strong>of</strong> a circuit is equal to ω 0 = ( where L and C are LC its inductance and capacity). The natural frequency <strong>of</strong> a sample with a thickness d is equal c to ω0 = (where ε and µ are a dielectric constant and a magnetic susceptibility <strong>of</strong> d εµ a medium). The natural frequencies <strong>of</strong> a thin metal or semiconductor layers with d = 1 ÷ 100 nm are situated in the spectral region from ultraviolet to infrared. Our calculations <strong>of</strong> the thickness dependencies <strong>of</strong> the indices <strong>of</strong> refraction n(d) and the coefficients <strong>of</strong> absorption α (d) <strong>of</strong> thin metal and semiconductor films based on our analogues <strong>of</strong> Fresnel’s formulas for absorbing media [1] and the experimental data <strong>of</strong> reflection and transmission for these materials show the resonance maxima <strong>of</strong> n(d) and the λ0 2πc resonance minima <strong>of</strong> α (d ) . All <strong>of</strong> them take place when d res = , ( λ0 = ). 2πn( d res ) ω0 Investigation show that silicon has the best emission ability among the investigated materials (Ag, Al, Fe, Si, Ge, Se, Te). Silver has greater negative absorption than silicon, but the luminescence decay in Ag (calculated coefficient <strong>of</strong> a time decay <strong>of</strong> a wave α 1 ) is α1 cn greater too. The condition =
SAINT-PETERSBURG, October 17 – 20, 2005 51 Fig.1. Dimension dependences <strong>of</strong> the coefficients <strong>of</strong> absorption α (d) <strong>of</strong> thin layers: х – tellurium; + - germanium; о – selenium; □ – silicon. The wavelength <strong>of</strong> the incident light is λ =580 nm. Fig.2. Dimension dependences <strong>of</strong> the coefficients <strong>of</strong> absorption <strong>of</strong> thin layers: □ - silver; ○ - aluminum; + - iron. The wavelength <strong>of</strong> the incident light is λ =546.1 nm.
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