CdBr2 nanocrystalline layers as nonlinear optical materials
A new type of nanomaterial for optoelectronic is proposed. As such a material cleaved nanolayers of layered CdBr2 single crystals is chosen. A principal possibility to prepare thin hexagonal single crystalline layers of CdBr2 nanocrystals (possessing 6H polytype) with thickness up to several nanometers was shown. The studies of the optical absorption clearly show an occurrence of the blue spectral shift for the absorption edge up to 30 nm. During illumination by the 5 ns nitrogen laser at the wavelength at about 337 nm below the energy band gap it was established a substantial increase of the photoinduced absorption coefficient up to 25 cm−1 at pump power density equal to about 1 GW cm−2. The maximal photoinduced effect was observed for the thinnest film possessing thickness about 4 nm. The linear electrooptical effect was maximal at ambient temperature.
KeywordsSpectral Shift CdI2 CdBr2 Pump Power Density Photoinduced Absorption
This work was supported in part by MTU through the Program PBS-814.
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