Computer-assisted infrared spectra interpretation for amorphous silicon alloys

Metallic nanoparticles detected by infrared spectroscopy

“…The infrared wavelength range, of the order of 10 µm or about 100 meV, is the range where atomic vibrations are observed. For example, the SiN stretching in Si 3 N 4 is calculated as occurring around 840 cm −1 [2]. We show here that metallic clusters with diameters in the nanometer range are at the origin of an absorption band located in the 7-20 µm range, i.e.…”

“…2. The wide band located between 650 and 1140 cm −1 is the signature of Si-N vibrations and corresponds to the Si 3 N 4 layer [2]. The other peak located at 450 cm −1 is attributed to Pt clusters.…”

Nonlinear optical properties of Ag nanoparticles embedded in Si 3 N 4

“…We assume first that the insulating Si 3 N 4 matrix does not contribute to the SFG process. Indeed, the Si-N vibration modes are located around 800 cm −1 [11] out of the investigated IR spectral range. Even if we consider a certain width of the Si-N vibration signal, it should decrease from 1000 to 1200 cm −1 , whereas the resonant signal intensity is increasing in the same frequency range.…”