Determination of the Molar Extinction Coefficient of Colloidal Selenium for Optical Characterization of Stabilized Nanoparticulate Dispersions

Group II-VI compounds have been investigated largely in last two decades due to their interesting optoelectronic properties. ZnTe, a member of this family, possesses a bandgap around 2.26eV. This material is now a day investigated in thin film form due to its potential towards various viable applications. In this paper, the authors report their investigations on the preparation of ZnTe thin films using vacuum evaporation technique and their structural and optical characterizations. The structural characterization, carried out using an X-ray diffraction (XRD) technique shows that ZnTe used in present case possesses a cubic structure. Using the same data, the micro strain and dislocation density were evaluated and found to be around 1.465×10-3lines-m2and 1.639×1015lines/m2respecctively. The optical characterization carried out in UV-VIS-NIR region reveals the fact that band gap of ZnTe is around 2.2eV in present case. In addition to this, it was observed that the value of bandgap decreases as the thickness of films increases. The direct transitions of the carries are involved in ZnTe. Using the data of UV-VIS-NIR spectroscopy, the transmission coefficient and extinction coefficient were also calculated for ZnTe thin films. Besides, the variation of extinction coefficient with wavelength has also been discussed here.

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Experimental Determination of the Absorption Cross-Section and Molar Extinction Coefficient of Colloidal CdSe Nanoplatelets

The Journal of Physical Chemistry C ◽

10.1021/acs.jpcc.5b09275 ◽

2015 ◽

Vol 119 (47) ◽

pp. 26768-26775 ◽

Cited By ~ 88

Author(s):

Aydan Yeltik ◽

Savas Delikanli ◽

Murat Olutas ◽

Yusuf Kelestemur ◽

Burak Guzelturk ◽

...

Keyword(s):

Experimental Determination ◽

Cross Section ◽

Extinction Coefficient ◽

Absorption Cross Section ◽

Molar Extinction Coefficient ◽

Absorption Cross

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THE COMBINED ELLIPSOMETRIC METHOD OF COMPLETE OPTICAL CHARACTERIZATION OF CRYSTALS. I. DETERMINATION OF THE ORIENTATION OF THE OPTICAL INDICATRIX

Electronics and Information Technologies ◽

10.30970/eli.15.11 ◽

2021 ◽

Vol 15 ◽

Author(s):

V. Belyukh ◽

B. Pavlyk

Keyword(s):

Optical Characterization ◽

Optical Indicatrix ◽

Ellipsometric Method

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Optical Characterization of AsxTe100−x Films Grown by Plasma Deposition Based on the Advanced Optimizing Envelope Method

Materials ◽

10.3390/ma13132981 ◽

2020 ◽

Vol 13 (13) ◽

pp. 2981 ◽

Cited By ~ 1

Author(s):

Dorian Minkov ◽

George Angelov ◽

Radi Nestorov ◽

Aleksey Nezhdanov ◽

Dmitry Usanov ◽

...

Keyword(s):

Refractive Index ◽

Extinction Coefficient ◽

Glass Substrate ◽

Plasma Deposition ◽

Optical Characterization ◽

The Other ◽

Semiconductor Film ◽

Average Thickness ◽

Envelope Method

Three AsxTe100−x films with different x and dissimilar average thickness d ¯ are characterized mainly from one interference transmittance spectrum T(λ = 300 to 3000 nm) of such film on a substrate based on the advanced optimizing envelope method (AOEM). A simple dual transformation of T(λ) is proposed and used for increasing the accuracy of computation of its envelopes T+(λ) and T−(λ) accounting for the significant glass substrate absorption especially for λ > 2500 nm. The refractive index n(λ) of As40Te60 and As98Te2 films is determined with a relative error <0.30%. As far as we know, the As80Te20 film is the only one with anomalous dispersion and the thickest, with estimated d ¯ = 1.1446 nm, ever characterized by an envelope method. It is also shown and explained why the extinction coefficient k(λ) of any of the three AsxTe100−x films is computed more accurately from the quantity Ti(λ) = [T+(λ)T−(λ)]0.5 compared to its commonly employed computation from T+(λ). The obtained results strengthen our conviction that the AOEM has a capacity for providing most accurate optical characterization of almost every dielectric or semiconductor film with d ¯ > 300 nm on a substrate, compared to all the other methods for characterization of such films only from T(λ).

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