Influence of photonic excitations on the electrical parameters of TlInS2 crystals

Hasanlı, Nızamı
The photo-excitation effect on the current transport mechanism in TlInS2 crystals has been studied by means of dark and illuminated conductivity measurements. The temperature-dependent electrical conductivity analysis in the temperature region of 110-340 K revealed the domination of the thermionic emission and the thermally assisted variable range hopping (VRH) of charge carriers above and below 160 K, respectively. Above 160 K, the conductivity activation energies in the dark are found to be 0.28 and 0.15 eV in the temperature regions of 340-240 K and 230-160 K, respectively. In the temperature region of 110-150 K, the dark variable range hopping analysis revealed a density of localized states of 1.99x 10(22) cm(-3)eV(-1), an average hopping distance of 0.53 nm and an average hopping energy of 79.65 meV. When the sample was photo-excited, the values of the conductivity activation energies, the density of localized states near the Fermi level and the average hopping energy were observed to decrease sharply with increasing illumination intensity. On the other hand, the average hopping distance increased with rising illumination intensity. Such behaviours were attributed to the Fermi level shift and/or trap density reduction by electron-hole recombination. (C) 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim


Influence of ion implantation on structural and photoconductive properties of Bridgman grown GaSe single crystals
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The structure and temperature dependent spectral photoconductivity of as-grown and N-and Si-implanted GaSe single crystals have been studied. It was observed that post-annealing results in a complete recovery of the crystalline nature that was moderately reduced upon implantation. The band edge is shifted in the implanted sample which is attributed to the structural modifications and continuous shallow levels introduced upon implantation and annealing. Our calculations showed that the trap density is increa...
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Hasanlı, Nızamı (Wiley, 2010-05-01)
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Effect of isomorphic atom substitution on the refractive index and oscillator parameters of TlInS2xSe2(1-x) (0.25 <= x <= 1) layered mixed crystals
Hasanlı, Nızamı (Wiley, 2010-11-01)
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The electrical resistivity and Hall coefficient of p-type TlGaTe2 crystals were measured in the temperature range of 110-320 K. The electrical resistivity, charge carrier density and Hall mobility data for the crystals have been analyzed by means of existing theories and models to determine the extrinsic energy levels, the carrier effective mass, the donor and acceptor concentrations and the dominant scattering mechanism in the crystal as well. The analysis of the temperature-dependent electrical resistivit...
Citation Formats
A. F. H. QASRAWI and N. Hasanlı, “Influence of photonic excitations on the electrical parameters of TlInS2 crystals,” CRYSTAL RESEARCH AND TECHNOLOGY, pp. 433–438, 2010, Accessed: 00, 2020. [Online]. Available: