Transmittance and reflectance i n s i t u measurements of semicontinuous gold films during deposition

Abstract

We have continuously measured in situ reflectance and transmittance of percolating gold films over the entire range of surface coverage P, in the IR regime (1.7 and 2.2 μm). The samples present similar optical and electrical behavior, when compared on a normalized thickness scale. In the fractal region, close to the percolation threshold, the optical properties show a linear dependence on the surface coverage parameter, in agreement with a renormalization argument previously suggested. A strong absorption (about 40%), whose origin is not well understood, is found in the fractal region. The interpretations previously proposed by other authors are not applicable. We conclude that geometrical effects must dominate the optical properties over a large range of surface coverage.

Electromagnetic field fluctuations and optical nonlinearities in metal-dielectric composites

“…In particular calculations the dynamic e!ective medium given by Eqs. (7.122) and (7.123) had been [89,90], solid lines our calculations. The frequency-dependent complex conductivity of gold was taken to be BA /(1!i ), where BA "0.7;10 s\ and "3;10\ s, in accordance with Ref.…”

Highly absorbing black Mg and rare-earth-Mg switchable mirrors

“…Furthermore, we show that this phenomenon is similar to the high absorption of light observed in metal-dielectric composites 27,28 such as Au-glass, [29][30][31] Ag-glass, 32 and Co-Al 2 O 3 . 33 Its origin is fundamentally different from that of other black materials such as microstructured Si 34 or Ni-P 35 for which a rough surface morphology is essential.…”

Synthesis of polymer–PbS nanocomposite by solar irradiation-induced thermolysis process and its photovoltaic applications

“…Due to its larger EBR, the quantum confinement effect could be observed to a much higher particle size and band-gap energy of PbS can be tuned from 0.41 to 2.3 eV by changing the mean nanocluster size [2]. These properties make PbS a very suitable candidate for infrared detection application [3], photography [4], Pb 2þ ion-selective sensors [5], display devices [6] and solar absorption [7]. In addition, PbS has been utilised as a photoresistance, diode lasers, humidity and temperature sensors, decorative and solar control coatings [8,9].…”