Multiphased (NaCl)x(KCl)y−x(KBr)1−y single crystals: ac conductivity activation energy versus bulk properties

Zn-rich and P-rich amorphous Zn3P2 thin films were prepared by co-evaporation of the excess element during the normal Zn3P2 deposition. X-ray diffraction techniques were used to investigate the structural properties and the crystallization process. Agglomeration of the excess element within the as-made amorphous Zn3P2 thin film accounted for the structural properties observed after annealing the sample. Electrical measurements showed that excess Zn reduces the conductivity activation energy and increases the conductivity, while excess P up to 15 at.% does not alter the electrical properties significantly.

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Magnetic properties of undoped and Co-doped n-type β–FeSi2.5 single crystals

Journal of Materials Research ◽

10.1557/jmr.2002.0429 ◽

2002 ◽

Vol 17 (11) ◽

pp. 2960-2965 ◽

Cited By ~ 4

Author(s):

E. Arushanov ◽

L. Ivanenko ◽

D. Eckert ◽

G. Behr ◽

U. K. Rößler ◽

...

Keyword(s):

Activation Energy ◽

Magnetic Properties ◽

Magnetic Susceptibility ◽

External Field ◽

Single Crystals ◽

Spin Glasses ◽

Paramagnetic Centers ◽

Temperature Dependent ◽

Paramagnetic Curie Temperature ◽

Co Doped

Results of magnetization and magnetic susceptibility measurements on undoped and Co-doped FeSi2.5 single crystals are presented. The temperature dependence of the magnetic susceptibility of the Co-doped sample in the range of 5–300 K can be explained by temperature-dependent contributions due to paramagnetic centers and the carriers excited thermally in the extrinsic conductivity region. The values of the paramagnetic Curie temperature and activation energy of the donor levels were estimated. It is also shown that the magnetic susceptibility of Co-doped samples cooled in zero external field and in a field are different. This resembles the properties of spin-glasses and indicates the presence of coupling between magnetic centers.

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Study on Low Temperature Conduction Mechanism of Al Doped ZnO/SiO2/ P-Si Heterojunction

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.904.363 ◽

2021 ◽

Vol 904 ◽

pp. 363-368

Author(s):

Xiao Yan Zhou ◽

Bang Sheng Yin

Keyword(s):

Activation Energy ◽

Impedance Spectroscopy ◽

Low Temperature ◽

Grain Boundaries ◽

Ac Conductivity ◽

Spray Pyrolysis Method ◽

Temperature Conductivity ◽

Calculated Activation Energy ◽

Doped Zno ◽

Temperature Conduction

The 3 at% Al doped ZnO thin films were deposited on p-Si substrate with a native SiO2 layer by spray pyrolysis method. Low temperature conduction behaviors were studied by analysis of impedance spectroscopy and low temperature ac conductivity. The results of impedance spectroscopy showed that the grain boundaries contributed to the resistivity of Al doped ZnO/SiO2/p-Si heterojunction. The calculated activation energy was 0.073 eV for grain boundaries. The equivalent circuit to demonstrate the electrical properties of Al doped ZnO/SiO2/p-Si heterojunction was a series connection of two parallel combination circuits of a resistor and a universal capacitor. Low temperature ac conductivity measurements indicated that the conductivity increased with temperature. Low temperature conductivity mechanism was electron conductivity, and the activation energy was 0.086 eV.

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Глубокие центры радиационных дефектов в монокристаллах CdZnTe, созданные потоком быстрых нейтронов

Физика и техника полупроводников ◽

10.21883/ftp.2018.03.45615.8373 ◽

2018 ◽

Vol 52 (3) ◽

pp. 322 ◽

Cited By ~ 1

Author(s):

С.В. Пляцко ◽

Л.В. Рашковецкий

Keyword(s):

Activation Energy ◽

Neutron Flux ◽

Fast Neutron ◽

Single Crystals ◽

Isothermal Annealing ◽

Fast Neutron Flux ◽

Photoluminescence Properties ◽

Radiation Induced ◽

Induced Defects

AbstractThe effect of a fast neutron flux (Φ = 10^14–10^15 cm^–2) on the electrical and photoluminescence properties of p -CdZnTe single crystals is studied. Isothermal annealing is performed ( T = 400–500 K), and the activation energy of the dissociation of radiation-induced defects is determined at E _D ≈ 0.75 eV.

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PHOTOELECTRIC PROPERTIES OF MnIn2S4 SINGLE CRYSTALS

Journal of Applied Spectroscopy ◽

10.47612/0514-7506-2021-88-6-967-969 ◽

2021 ◽

Vol 88 (6) ◽

pp. 967-969

Author(s):

N. N. Niftiyev

Keyword(s):

Activation Energy ◽

Temperature Dependence ◽

Single Crystals ◽

Spectral Distribution ◽

Photoconductivity Spectrum ◽

Intracenter Transition ◽

Photoelectric Properties ◽

Impurity Photoconductivity ◽

Donor Defect

The spectral distribution of the photoconductivity and the temperature dependence of the photocurrent of MnIn2S4 single crystals are investigated. The intrinsic, impurity photoconductivity and a maximum at an energy of 2.69 eV, which is associated with the intracenter transition of Mn2+ ions (6A1→4A1), are revealed in the photoconductivity spectrum. The region of the wavelengths of 600–1000 nm appears with an excess of manganese in the crystals and is caused by a donor defect. At temperatures of 80—145 K, the increase in the photocurrent is associated with the thermal depletion of the adhesion levels. The activation energy of the adhesion levels is determined.

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The Compression Creep Behavior of Ni3Al-X Single Crystals

MRS Proceedings ◽

10.1557/proc-213-623 ◽

1990 ◽

Vol 213 ◽

Cited By ~ 6

Author(s):

Seiji Miura ◽

Tohru Hayashi ◽

Mitsuhiro Takekawa ◽

Yoshinao Mishima ◽

Tomoo Suzuki

Keyword(s):

Activation Energy ◽

Single Crystals ◽

Power Law ◽

Creep Behavior ◽

Creep Resistance ◽

Constant Strain Rate ◽

State Equation ◽

Ternary Alloys ◽

Plastic Behavior ◽

Compression Tests

ABSTRACTCompressive creep behavior is investigated in ternary Ni3Al single crystals containing Ti, Si, Hf and Cr with stress axes parallel to the crystallographic orientation near [001]. Then a comparison is made with the results of high temperature compression tests under a constant strain rate for the same orientation where plastic behavior is characterized by a distinct yield drop followed by steadystate deformation. It is found that the deformation mechanism for the two cases is identical, namely octahedral viscous flow being expressed by the state equation of the power-law type with a stress exponent of about 3 to 4. The effect of offstoichiometry on the creep resistance is then examined in Ni3(Al,5 at%Ti) alloys with different Ni concentrations. The results support the observation in the polycrystalline compound where the creep resistance increases with Ni concentration on both sides of stoichiometry exhibiting a discontinuity at stoichiometry. Finally, the apparent activation energy in the power-law type state equation for the steady state creep deformation is estimated for all the ternary alloys examined. They are in general in good agreement with that for diffusion of ternary elements in Ni3Al. However, the relative magnitude of the value can not simply be compared since the activation energy depends on deviations from stoichiometry.

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