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Article Citation - WoS: 7Citation - Scopus: 9Thermoluminescence Study in Cu3ga5< Single Crystals: Application of Heating Rate and tm< Methods(Elsevier Science Bv, 2018) Isik, M.; Gasanly, N. M.; Gasanova, L. G.; Mahammadov, A. Z.Cu3Ga5S9 semiconducting single crystals were investigated using thermoluminescence (TL) measurements in 10-300 K temperature region. In the TL glow curve, one peak starting to appear at the instant temperature is increased from 10 K and another peak, which is broader than a general individual TL peak, were observed. The broad peak around 66 K was investigated using T-m-T-stop experimental method to understand whether or not this peak is composed of more than one individual peaks or continuously distributed traps. Curve fitting, initial rise and peak shape methods were used for acceptable TL curves to be analyzed. TL curves in T-m-T-stop method indicated that observed peaks are due to the existence of quasi-continuous distribution of traps. Structural characterizations of Cu3Ga5S9 single crystals were studied using x-ray diffraction and energy dispersive spectroscopy measurements. The crystal structure, lattice parameters and atomic composition of the elements were reported in the present paper.Article Citation - WoS: 1Citation - Scopus: 1Analysis of Glow Curve of Gas0.5se0.5< Single Crystals(Elsevier Science Bv, 2015) Isik, Mehmet; Delice, Serdar; Gasanly, NizamiCharacterization of shallow trapping centers in GaS0.5Se0.5 crystals grown by a Bridgman method was carried out in the present work using thermoluminescence (TL) measurements performed in the low temperature range of 10-300 K. The activation energies of the trapping centers were obtained under the light of results of various analysis methods. The presence of three trapping centers located at 6, 30 and 72 meV was revealed. The analysis of the experimental glow curve gave reasonable results under the model that assumes slow retrapping which states the order of kinetics as b=1. Heating rate dependence of the observed TL peaks was studied for the rates between 0.4 and 1.0 K/s. Distribution of the traps was also investigated using an experimental technique based on the thermal cleaning of centers giving emission at lower temperatures. The distributed levels with activation energies increasing from 6 to 136 meV were revealed by increasing the stopping temperature from 10 to 52 K. (C) 2015 Elsevier B.V. All rights reserved.Article Citation - WoS: 8Citation - Scopus: 8Photo-Transferred Thermoluminescence of Shallow Traps in Β-Irradiated Beo Ceramics(Elsevier Science Bv, 2017) Isik, M.; Bulur, E.; Gasanly, N. M.Photo-transferred thermoluminescence signals from beryllium oxide (BeO) ceramics were measured in the low temperature range of 10-300 K. Samples irradiated at room temperature using a Sr-90/Y-19 beta source were cooled down to 10 K and trapped charges were photo-transferred at this low temperature using the light from a high power blue LED emitting at similar to 470 nm (2.6 eV). Thermoluminescence glow curve recorded at 0.2 K/s heating rate exhibited three peaks around 90, 160 and 185 K. The analyses of the TL peaks of the glow curve were accomplished using curve fitting, differential and peak shape methods. Results obtained from these techniques are in good agreement about the presence of three trapping centers in BeO ceramics with activation energies of 0.24, 0.48 and 0.56 eV. Moreover, the analyses indicated that first-order kinetics (slow retrapping) is the dominant mechanism in the luminescence process. Heating rate dependence of the glow curves was also investigated between 0.2 and 0.8 K/s rates. (C) 2017 Elsevier B.V. All rights reserved.Article Citation - WoS: 48Citation - Scopus: 48Gd-Doped Zno Nanoparticles: Synthesis, Structural and Thermoluminescence Properties(Elsevier Science Bv, 2019) Isik, M.; Gasanly, N. M.Structural and thermoluminescence (TL) properties of Gd-doped ZnO nanoparticles were investigated in the present study. TL glow curves recorded in the 10-300 K range presented three overlapped peaks around 56, 110 and 155 K for undoped ZnO nanoparticles. The Gd-doping to the ZnO nanoparticles resulted in shift of peak maximum temperatures to lower values and decrease of activation energies associated with the observed peaks. Activation energies of trapping centers were also reported. Taking into account the previously reported studies on defect characterization of ZnO compound, revealed centers were associated with interstitial defects. Structural characteristics of the synthesized nanoparticles were investigated by x-ray diffraction and scanning electron microscopy measurements.Article Citation - WoS: 7Citation - Scopus: 7Annealing Effect on the Low Temperature Thermoluminescence Properties of Gase Single Crystals(Elsevier Science Bv, 2014) Isik, M.; Hadibrata, W.; Gasanly, N. M.Trapping centers in as-grown GaSe single crystals have been investigated by thermoluminescence (TL) measurements in the temperature range of 30-300 K. The analysis of the observed peaks in TL glow curve to determine the activation energies of the associated centers were accomplished using curve fitting, initial rise and peak shape methods. Activation energies of the revealed four trapping centers obtained from various methods were in good agreement with each other on the energy values of 0.14, 0.18, 0.24 and 037 eV. The annealing effect on the TL properties of the GaSe single crystals was also studied for the annealing temperature of 500 degrees C. It was observed that annealing significantly decreased the U intensity and shifted the observed peaks to lower temperature resulting with smaller activation energy values. The distribution of the trapping centers with most intensive peak was also studied on both as-grown and annealed crystals. (C) 2014 Elsevier B.V. All rights reserved.
