Proceedings of Topical Meeting on Optoinformatics (pdf-format, 1.21 ...

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 =