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Articles 1 - 30 of 61
Full-Text Articles in Physics
Study Of A = 100-150 Superdeformed Mass Region By Using Two-Parameterformula, Vidya Devi, Jagjit Singh Matharu
Study Of A = 100-150 Superdeformed Mass Region By Using Two-Parameterformula, Vidya Devi, Jagjit Singh Matharu
Turkish Journal of Physics
Empirical formulae of rotational spectra consisting two parameters, such as single-term energy formula, E = aJb for spin J , and ab formula, were used to study the different features of superdeformed band in A = 100-150 mass region nuclei. The nuclear kinematic and dynamic moment of inertia for the ground-state rotational bands were calculated for this purpose and both showed gradual rise with rotational frequency. The study of ΔI = 2 staggering effects in the γ-ray energies, where the two sequences J = 4i; 4i + 1 and J = 4i + 2, (i = 0; 1; ...) are …
Effects Of Cooling Rate On The Atomic Structure And Glass Formation Process Of Co90 Zr10 Metallic Glass Investigated By Molecular Dynamics Simulations, Murat Çeltek, Sedat Şengül
Effects Of Cooling Rate On The Atomic Structure And Glass Formation Process Of Co90 Zr10 Metallic Glass Investigated By Molecular Dynamics Simulations, Murat Çeltek, Sedat Şengül
Turkish Journal of Physics
In this study, the atomic structure and the glass formation process of Co90 Zr10 metallic glass alloy were studied by molecular dynamic simulation based on the embedded atom method using four different cooling rates. The average atomic volume and the potential energy of the system were observed to be strongly dependent on the cooling rate during rapid solidification, and the glass transition temperature decreased with decreasing cooling rate. The radial distribution functions and the structure factors derived from molecular dynamics simulations at 300 K agreed well with the experimental and other molecular dynamics results. The coordination numbers calculated at 300 …
Effect Of Left-Handed Materials In Surface Plasmon Excitation And Propagationlength, Ari̇f Engi̇n Çeti̇n
Effect Of Left-Handed Materials In Surface Plasmon Excitation And Propagationlength, Ari̇f Engi̇n Çeti̇n
Turkish Journal of Physics
We investigated the dispersion relation of surface plasmons (SPs) excited in a medium comprised of a left-handed material (LHM) layer. We investigated different light polarizations in SP excitation along an LHM-metal interface. We studied SP excitation through a classical Kretschmann geometry, employing an LHM interlayer between a dielectric and a metal layer. Using this three-layer configuration, we investigated the effect of LHM medium on characterizing SP propagation length, which is directly related to the energy of the surface waves.
Design And Test Of An Apparatus For Transient Measurements Of The Thermalconductivity And Volumetric Heat Capacity Of Solids, Florian Gather, Ekrem Güneş, Peter J. Klar
Design And Test Of An Apparatus For Transient Measurements Of The Thermalconductivity And Volumetric Heat Capacity Of Solids, Florian Gather, Ekrem Güneş, Peter J. Klar
Turkish Journal of Physics
Knowledge of the thermal conductivity (κ) of solids is crucial for all thermoelectric devices. A new approach in transient measurement to determine this value as well as electric conductivity (σ) and the Seebeck coefficient (S) is presented here. This approach can be combined with current steady-state methods. A cylindrical sample is mounted between two heat-flux sensors that can be heated or cooled at their outer ends. The input signals defining the heat fluxes at the sensors can be any arbitrary function of time, although some waveforms yield more valid results. The method is evaluated by employing a one-dimensional numerical model …
Autonomous Piston Engine Guided By The Transduction Of Radiation Pressure Inoptomechanical Brownian Motors, Yusuf Gül
Turkish Journal of Physics
We consider the autonomous piston engine in a coupled cavity scheme in an optomechanical setup. Treating the radiation field as working fluid, we investigate the transduction of virtual photons due to ground state excitations. Rabi-like energy splittings and Casimir effect are shown by avoided crossing in the eigenfunction spectrum. Second order coherence functions are employed to analyze the bunching of the cavity and mechanical mode in optomechanical implementation of Brownian motors. The imbalance in occupation numbers of the working modes is investigated for the power for work extraction. We explore the guidance of the radiation field in work extraction. We …
Modified Newton's Gravitational Law From Deformed Poisson Bracket, Ch'ng Han Siong
Modified Newton's Gravitational Law From Deformed Poisson Bracket, Ch'ng Han Siong
Turkish Journal of Physics
In this paper, we obtain the modified Newton's gravitational law from deformed Poisson bracket motivated by the generalized uncertainty principle. The modified Newton's gravitational law that we obtain contains a term that plays an important role only in the regime of first order in $\bar{\beta}$. In the ordinary situation or condition, the modified Newton's gravitational law reduces to the conventional Newton's gravitational law.
Lorentz-Violating Effects In Single W Boson Production At The Lhc, Serdar Spor, İnanç Şahi̇n
Lorentz-Violating Effects In Single W Boson Production At The Lhc, Serdar Spor, İnanç Şahi̇n
Turkish Journal of Physics
We investigate the Lorentz-violating effects of Standard Model Extension (SME) in single W boson production process pp → pγp → p W- q' X at the Large Hadron Collider (LHC). We employ the Weizsacker-Williams approximation for photons emitted from one of the incoming proton beams and consider γq → W- q' as a subprocess in the proton-proton collision. The behavior of the differential cross-section for various orientations of the constant background fields is obtained by taking into account longitudinal and transverse polarization states of the final W bosons.
Synthesis, Characterization, And Magnetic Properties Of Nanosizedzn0.5co0.5erxfe2-Xo4 Prepared By Coprecipitation Method, Zouheir Bitar, Doaa El-Said Bakeer, Ramadan Awad
Synthesis, Characterization, And Magnetic Properties Of Nanosizedzn0.5co0.5erxfe2-Xo4 Prepared By Coprecipitation Method, Zouheir Bitar, Doaa El-Said Bakeer, Ramadan Awad
Turkish Journal of Physics
In the present work, the effect of doping zinc cobalt ferrite by different concentrations of Er3+ on structural, optical, and magnetic properties was studied. Nanosized Zn0.5Co0.5ErxFe2-xO4 (0 ≤ x ≤ 0.2) was synthesized by the coprecipitation method. XRD analysis confirmed the formation of one phase face FCC spinel structure belonging to the Fd3m space group. TEM exhibited that the particle size decreased with the increase of Er3+ content, which is in agreement with XRD results. Two significant absorption bands from FTIR spectra were observed between 400 and 600 cm-1. The band gap energy value obtained from UV-Vis increased with the …
First- And Second-Law Thermodynamic Analyses Of A Combined Natural Gas Cyclepower Plant: Sankey And Grossman Diagrams, Mehmet Onur Karaağaç, Ahmet Kabul, Hasan Oğul
First- And Second-Law Thermodynamic Analyses Of A Combined Natural Gas Cyclepower Plant: Sankey And Grossman Diagrams, Mehmet Onur Karaağaç, Ahmet Kabul, Hasan Oğul
Turkish Journal of Physics
The natural gas combined cycle power plant is one of the best options for generating electricity due to its use of low carbon fuels, high efficiency, and operational flexibility. These plants consist of a combination of Brayton and Rankine cycles, and investigation of these cycles is performed in this paper. Here the parameters of pressure and temperature used in the calculations are taken from a combined cycle power plant. The net power output of the system at 25 °C ambient temperature and 101.325 kPa pressure was calculated as 45 and 12 MW for Brayton and Rankine cycles, respectively. In addition, …
Effect Of Al Doping On The Magnetic And Elastic Properties Of Fe65 Ni35 Invar Alloys, Asli Çakir
Effect Of Al Doping On The Magnetic And Elastic Properties Of Fe65 Ni35 Invar Alloys, Asli Çakir
Turkish Journal of Physics
Invar alloys have great importance due to their low thermal expansion coefficient. The effect of Al doping on Fe65 Ni35 Invar alloy was investigated by temperature-dependent magnetization and elastic modulus measurements. First, 0.44 at% and 2.24 at% of Al were substituted for Ni. Then X-ray diffraction measurements, Rietveld refinements, and scanning electron microscopy studies were performed to understand the effect of Al-doping on the face-centered cubic structure. The elastic modulus of Fe65 Ni35 and the Al-doped samples were measured in the temperature range 300 ≤ T ≤ 870 K using impulse excitation. The temperature dependence of magnetization and elastic modulus …
Enhanced Efficiency Of Cds/P3ht Hybrid Solar Cells Via Interfacial Modification, Sali̇h Yilmaz, İsmai̇l Polat, Murat Tomaki̇n, Ahmet Ünverdi̇, Emi̇n Bacaksiz
Enhanced Efficiency Of Cds/P3ht Hybrid Solar Cells Via Interfacial Modification, Sali̇h Yilmaz, İsmai̇l Polat, Murat Tomaki̇n, Ahmet Ünverdi̇, Emi̇n Bacaksiz
Turkish Journal of Physics
The present paper examines the effects of surface modification of CdS with diverse dyes on fabricated CdSbased hybrid solar cells. The X-ray diffraction results showed that CdS thin films had a hexagonal phase with a preferred orientation along the (101) plane. Scanning electron microscopy indicated that the CdS specimen was composed of a granular structure while a P3HT layer was formed from tiny grains. Band gaps of the CdS thin films and the P3HT layer were 2.45 eV and 1.98 eV, respectively. The absorption spectra showed that different dye loading caused an increase in the absorbance of CdS thin films …
On Memory Effect In Modified Gravity Theories, Ercan Kiliçarslan
On Memory Effect In Modified Gravity Theories, Ercan Kiliçarslan
Turkish Journal of Physics
In this work, we discuss the gravitational memory effect in higher derivative and infinite derivative gravity theories and give the detailed relevant calculations whose results were given in our recent works. We show that the memory effect in higher derivative gravity takes the same form as in pure GR at large distances, whereas at small distances, the results are different. We also demonstrate that, in infinite derivative gravity, the memory is reduced via error function as compared to Einstein's gravity. For the lower bound on the mass scale of nonlocality, the memory essentially reproduces the usual GR result at distances …
Pressure-Induced Structural Phase Transition And Electronic Structure Of In$_{1-X}$Ga$_{X}$P Alloys: A Dft Study, Kabita Khoirom, Indrajit Sharma, Brojen Singh, Ramkumar Thapa
Pressure-Induced Structural Phase Transition And Electronic Structure Of In$_{1-X}$Ga$_{X}$P Alloys: A Dft Study, Kabita Khoirom, Indrajit Sharma, Brojen Singh, Ramkumar Thapa
Turkish Journal of Physics
We present the density functional calculation to study the pressure-induced structural phase transition and electronic structure of In$_{1-x}$Ga$_{x}$P ($x =$ 0.0, 0.25, 0.5, 0.75, 1) alloys. We report the optimized structural parameters such as lattice constant, bulk modulus, and derivative of the bulk modulus of the alloys. Our calculation confirms that the alloys in the zinc-blende structure are more stable than in the rock-salt structure. The phase transition study from zinc-blende to rock-salt under pressure shows that the transition pressure increases with an increase in doping concentration. The energy band diagram of the alloys in the zinc-blende phase reveals a …
Theoretical Description Of The Two-Color Photoelectron Spectra Process Of Hydrogen: Comparison Between Tdse Calculation And Kroll And Watson Approach, Souhaila Chaddou, Soumia Chqondi, Abdelmalek Taoutioui, Abdelkader Makhoute
Theoretical Description Of The Two-Color Photoelectron Spectra Process Of Hydrogen: Comparison Between Tdse Calculation And Kroll And Watson Approach, Souhaila Chaddou, Soumia Chqondi, Abdelmalek Taoutioui, Abdelkader Makhoute
Turkish Journal of Physics
We present a theoretical study of the main characteristics of two-color photoionization of hydrogen atoms by short strong laser pulses. Our numerical approach is performed by numerically solving the time-dependent Schrödinger equation for a hydrogen atom interacting with Ti:sapphire laser radiation combined with its 15th harmonic. The energy spectra obtained by the direct numerical solution of the Schrödinger equation are compared with those given by the Kroll and Watson perturbative approach. This comparison allows us to check the reliability of the latter approximation.
Determination Of Effective Resonance Energies For The $^{185}$Re(N,$\Gamma )^{186}$Re And $^{187}$Re(N,$\Gamma )^{188}$Re Reactions By Cadmium Ratio Method, Mustafa Güray Budak
Determination Of Effective Resonance Energies For The $^{185}$Re(N,$\Gamma )^{186}$Re And $^{187}$Re(N,$\Gamma )^{188}$Re Reactions By Cadmium Ratio Method, Mustafa Güray Budak
Turkish Journal of Physics
The effective resonance energy ($\bar{E}_{r})$ values for the $^{185}$Re(n,$\gamma )^{186}$Re and $^{187}$Re(n,$\gamma )^{188}$Re reactions were measured by using the cadmium ratio method. $^{197}$Au and $^{98}$Mo isotopes were selected as dual monitors to determine the epithermal neutron spectrum shape factor in the irradiation sites of a 37 GBq $^{241}$Am-Be neutron source. The analytical grade rhenium(VII) oxide samples were diluted with Al$_{2}$O$_{3}$ powder to reduce neutron self-shielding effects, and they were put into 1-mm thick small cylindrical polytetrafluoroethylene (PTFE) boxes. Samples were irradiated in a $^{241}$Am-Be neutron source. The activation produced in the irradiated samples was measured in close-counting geometry on the …
Higher-Order Differential Cross Section Calculation For The Associated Production Ofa W Boson And Jets In The Electron Decay Channel At A Center-Of-Mass Energy Of 13tev In Proton-Proton Collisions, Kadi̇r Öcalan
Turkish Journal of Physics
Higher-order cross sections for the production of a W boson in association with jets in the electron decay channel are presented in this study. Cross sections were calculated in a fully differential way using a computational framework based on proton-proton collisions at a center-of-mass energy of 13 TeV. The differential cross section predictions in the fiducial phase-space were compared at next-to-leading order (NLO) and next-to-NLO (NNLO) in perturbative quantum chromodynamics (pQCD). The differential results are reported for the variables including the jet multiplicity, the invariant mass of the W boson, transverse momentum, the jet rapidity, and the electron pseudorapidity that …
Electroweak Decays Of Unflavored Mesons In Poincaré Covariant Quark Model, Vadzim Haurysh, Viktor Andreev
Electroweak Decays Of Unflavored Mesons In Poincaré Covariant Quark Model, Vadzim Haurysh, Viktor Andreev
Turkish Journal of Physics
This work presents the procedure for obtaining integral representation of the radiative decay constant in the Poincaré-covariant quark model, based on Poincaré-invariant quantum mechanics. In the course of the work the authors give numerical estimates of magnetic moments of the light quarks ($u,d,s$) from the $V\rightarrow P\gamma$ decay, based on the calculation method of the observer that was previously developed. This technique is generalized in the case of the decay $P\rightarrow V\gamma$ with further numerical calculation of mixing angles $\eta-\eta^{\prime}$ of pseudoscalar mesons. Within the framework of the offered approach, we obtain a self-consistent model that describes radiative and leptonic …
Effect Of Low-Temperature Oxidation On The Properties Of Tivn/Vn Multilayer Coatings, Merve Ertaş Uslu, Özge Doğan, Leyla Çolakerol Arslan
Effect Of Low-Temperature Oxidation On The Properties Of Tivn/Vn Multilayer Coatings, Merve Ertaş Uslu, Özge Doğan, Leyla Çolakerol Arslan
Turkish Journal of Physics
An extensive study of the surface oxidation process on the properties of TiVN/VN multilayer coatings deposited by RF magnetron sputtering on Mg alloys was performed. TiVN/VN multilayer coatings with a total thickness of 660 nm and different layer numbers of 5, 11, and 33 were oxidized by annealing at 450K under partial oxygen pressure. Electronic, mechanical, and tribological properties of these coatings were characterized by X-ray photoelectron spectroscopy (XPS), scanning electron microscope, nanoindentation measurements, and scratch tester. The experimental results showed that the oxidation of TiVN/VN multilayer coatings leads to better performance in terms of surface roughness, hardness, and wear. …
Total Sunspot Number Calculation Based On Flare Production Potential Of Sunspot Groups: Reconstruction Of Ssn And Its Relation To Some Geomagnetic Indices, Ahmet Burak Karslioğlu, Burçi̇n Dönmez, Ali̇ Kilçik
Total Sunspot Number Calculation Based On Flare Production Potential Of Sunspot Groups: Reconstruction Of Ssn And Its Relation To Some Geomagnetic Indices, Ahmet Burak Karslioğlu, Burçi̇n Dönmez, Ali̇ Kilçik
Turkish Journal of Physics
In this study, we modified the previously introduced X-ray flare production potential (FPP) of each modified Zurich sunspot group based on its X-ray flare peak flux. Then, using these FPPs, the daily total sunspot number (Zurich number) calculation equation was modified; thus, new sunspot number data (CRz) were produced. We also compared ISSN and CRz with some geomagnetic indices (Dst, the maximum CME speed, and Ap indices). We found that the CRz data describe the geomagnetic indices quite well compared to ISSN. By using the regression equation between CRz and the sunspot area, the CRz dataset was recalculated back to …
The Influence Of Crosslinking Temperature On The Spectroscopic, Thermal, And Mechanical Properties Of Poly(Vinyl Alcohol)/Zeolite Composites, Cenk Denktaş
Turkish Journal of Physics
The aim of this study was to understand the effect of crosslinking temperature on the spectroscopic, thermal, and mechanical properties of poly(vinyl alcohol) (PVA)/zeolite composites. The PVA nanocomposite films were prepared using the solvent casting method with tartaric acid as the crosslinker. The changes in the structures of pure PVA film and powder clinoptilolite (CL) and nanocomposite films were analyzed by means of ATR-FTIR spectroscopy. The effect of both crosslinking temperature and CL on the composite films prepared by the addition of constant CL to the polymer matrix at different crosslinking temperatures (series II) and pure PVA films prepared with …
The Effect Of Phenylboronic Acid-Based Self-Assembled Monolayers On Theperformance Of Organic Field-Effect Transistors (Ofets), Tuğbahan Yilmaz Aliç
The Effect Of Phenylboronic Acid-Based Self-Assembled Monolayers On Theperformance Of Organic Field-Effect Transistors (Ofets), Tuğbahan Yilmaz Aliç
Turkish Journal of Physics
The dielectric/semiconductor interface is one of the most important components strongly affecting the performance of organic field-effect transistors (OFETs). To improve OFET parameters, we applied a series of phenylboronic acid derivatives as self-assembly molecules between dielectric and organic semiconductor layers. Device performance parameters, especially threshold voltage, current on/off ratio, and subthreshold slope, were improved. To elucidate the mechanism, dielectric/semiconductor interfaces were analyzed using atomic force microscope and contact angle techniques.
Thin-Shell Wormholes From Kiselev Black Holes, Peter Kuhfittig
Thin-Shell Wormholes From Kiselev Black Holes, Peter Kuhfittig
Turkish Journal of Physics
This paper discusses the theoretical construction of thin-shell wormholes from Kiselev black holes. We assume a barotropic equation of state for the exotic matter on the shell. While most of these wormholes are unstable to linearized radial perturbations, a limit argument is used to show that under certain conditions, stable solutions can be found.
Nonlinear Frequency Conversion Of Light Inside A Microcavity, Emre Yüce
Nonlinear Frequency Conversion Of Light Inside A Microcavity, Emre Yüce
Turkish Journal of Physics
Changing the color of light in a small mode volume is essential for applications that require on-chip operation. Microcavities are profound structures given their property to confine light in a small mode volume. Here, I numerically investigate the frequency conversion of light in a microcavity and show that the frequency converted light intensity is distinguished from an open medium such as an optical fiber or a nonlinear crystal. I observe that the frequency converted light intensity increases with increased rate of change of the refractive index of the microcavity. Notably, this study shows that the intensity of the frequency converted …
Method For Determination Of Water Hammer Conditions And Consequences Inpressurizers Of Nuclear Reactors, Vladimir Skalozubov, Oleg Chulkin, Denis Pirkovskiy, Igor Kozlov, Yuriy Komarov
Method For Determination Of Water Hammer Conditions And Consequences Inpressurizers Of Nuclear Reactors, Vladimir Skalozubov, Oleg Chulkin, Denis Pirkovskiy, Igor Kozlov, Yuriy Komarov
Turkish Journal of Physics
Results of known experimental and computed studies of conditions for water hammers (WHs) in reactor pressurizers are analyzed. It is found that when emergency opening of pilot-operated safety valves of the pressurizers of nuclear reactors happens, WHs can be generated on pressurizer elements, and amplitudes of hydrodynamic load pulses significantly override the limiting values. An original method for determination of the WH conditions and consequences in the case of emergency filling of the pressurizers of nuclear reactors is proposed. Unlike the traditional Joukowski formula, the presented method considers the key features and effects of the WH conditions and consequences in …
Application Of The Fractional Oscillator Model To Describe Damped Vibrations, Sergo Rekhviashvili, Arsen Pskhu, Praveen Agarwal, Shilpi Jain
Application Of The Fractional Oscillator Model To Describe Damped Vibrations, Sergo Rekhviashvili, Arsen Pskhu, Praveen Agarwal, Shilpi Jain
Turkish Journal of Physics
We consider a model of damped vibrations based on fractional differentiation. The model given is completely consistent with the classical model of vibration with viscous damping. We find the relation between the order of fractional differentiation in the equation of motion and Q-factor of an oscillator. The proposed approach seems more appropriate for the physical nature of the described system. The experiment with a vibrating piezoelectric plate, performed as part of the study, showed good agreement with the model and confirmed that the fractional oscillator model can be used to describe strongly damped vibrations.
Emission Processes Of The Interaction Between The Quantum Well And Donor Delta Layer In Heterostructures For Phemts, Yana Ivanova, George Yakovlev, Vasily Zubkov, Anna Solomnikova
Emission Processes Of The Interaction Between The Quantum Well And Donor Delta Layer In Heterostructures For Phemts, Yana Ivanova, George Yakovlev, Vasily Zubkov, Anna Solomnikova
Turkish Journal of Physics
We present experimental and theoretical investigations of pHEMT heterostructures with AlGaAs/InGaAs/GaAs quantum wells (QWs) and/or a delta-doped layer, which can be used as active regions in transistors operating in the 4-18 GHz frequency range. Using the electrochemical capacitance-voltage setup ECV Pro we, for the first time, experimentally observed a concentration peak from the near-surface delta layer of the pHEMT structure together with a peak of QW enrichment. The capacitance of the electrolyte-semiconductor contact was measured by Agilent LCR-meter, which was connected to the electrochemical cell of ECV Pro through a specially designed relay module. Using numerical simulation of the electronic …
Effect Of Annealing Temperature On Structural, Electrical, And Uv Sensingcharacteristics Of N-Zno/P-Si Heterojunction Photodiodes, Şenol Kaya
Turkish Journal of Physics
The aim of this study is to investigate the influences of annealing temperature on initial device characteristics and their correlations with ultraviolet (UV) radiation sensitivity of n-type zinc oxide/p-silicon (n-ZnO/p-Si) heterojunction photodiodes. Evolutions on the crystalline structure, surface morphology, ideality factor, barrier potential, interface state density, and donor concentration were systematically analyzed during the initial device characterizations before testing the UV sensitivities of the photonic devices. The results demonstrate that the sensitivity of each n-ZnO/p-Si photodiode annealed at various temperatures was linearly correlated with different UV illumination intensities. The devices annealed at 750 ºC and 550 ºC exhibit more sensitive …
Comparison Of Geometric And Drive-Induced Nonlinearities In Doubly Clamped,Thermoelastic Nanoelectromechanical Systems, Mehmet Seli̇m Hanay
Comparison Of Geometric And Drive-Induced Nonlinearities In Doubly Clamped,Thermoelastic Nanoelectromechanical Systems, Mehmet Seli̇m Hanay
Turkish Journal of Physics
The performance of resonant sensors based on nanoelectromechanical systems depends critically on the maximum amplitude of oscillation reached in the linear regime. The maximum linear amplitude is determined by nonlinear mechanisms that can originate from the material, geometric and transduction mechanism related factors. Here we compare the two competing effects, the geometric and drive-induced nonlinearities, for a commonly used device family, the thermoelastically driven, doubly clamped beams. We find that the geometric nonlinearity dominates for most of the device designs used in the literature, however the drive-induced nonlinearity becomes the determining factor for thicker beams with small electrode lengths.
Localizable Entanglement Of Isotropic Antiferromagnetic Spin-1/2 Chain, İzzet Paruğ Duru, Şahi̇n Aktaş
Localizable Entanglement Of Isotropic Antiferromagnetic Spin-1/2 Chain, İzzet Paruğ Duru, Şahi̇n Aktaş
Turkish Journal of Physics
The bounds of entanglement on antiferromagnetic (AF) isotropic Heisenberg spin-1/2 chain including dipole- dipole interaction (D) were investigated. The Quantum Monte Carlo method based on loop algorithm was employed to calculate the two-spin and single-spin expectation values mediating the lower and upper bounds. It was revealed that D and Bz (the applied magnetic field) were pivotal parameters in controlling either entanglement creation/extinction or entanglement enhancement/weakening. Rival regions indicated a revival phenomenon depending on the temperature for various strengths of D which also showed a nonmonotonic behavior under certain Bz identifying critical points. Even if thermal agitations break the stability of …
Elaboration And Study Of Structural And Optical Properties Of Aubr Nanocrystalsdispersed In Kbr Single Crystals, Hanane Zaioune, Fouzia Zehani, Noureddine Boutaoui, Badis Khennaoui
Elaboration And Study Of Structural And Optical Properties Of Aubr Nanocrystalsdispersed In Kbr Single Crystals, Hanane Zaioune, Fouzia Zehani, Noureddine Boutaoui, Badis Khennaoui
Turkish Journal of Physics
The structural and optical properties of the AuBr nanocrystals embedded in the KBr single crystals grown by the Czochralski method were studied using several techniques. The X-ray diffraction reveals their formation and incorporation. The crystallite average radii calculated from XRD using the Scherrer's formula was found to vary between 19 and 39 nm. The photoluminescence spectra obtained on these same samples present an emission band located at 1.91 eV (650 nm), which can be attributed to the orange luminescence of AuBr nanocrystals. However, the photoluminescence excitation measurements of these nanocrystals exhibit an excitation band located at 3.44 eV (360 nm), …