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Full-Text Articles in Physics

Analysis Of Chaotic And Regular Behavior Of Matinyan-Yang-Mills-Higgshamiltonian System, Engi̇n Kandiran, Avadi̇s Si̇mon Hacinliyan Jan 2020

Analysis Of Chaotic And Regular Behavior Of Matinyan-Yang-Mills-Higgshamiltonian System, Engi̇n Kandiran, Avadi̇s Si̇mon Hacinliyan

Turkish Journal of Physics

In this study we analyze the Matinyan-Yang-Mills-Higgs (MYMH) system, based on semiclassical solutions to a Yang-Mills model, using Poincaré surfaces of section and the method of averaging. To investigate the possible chaotic behavior for the system, we simulate the trajectories of the system and calculate the Lyapunov exponents. We observe that the system displays weakly chaotic behavior. We search for the existence of approximately conserved quantities for the system using the method of averaging. In this way, we show the existence of four fixed points where period orbits exist.


Octonion Form Of Duality-Invariant Field Equations For Dyons, Mustafa Emre Kansu, Murat Tanişli, Süleyman Demi̇r Jan 2020

Octonion Form Of Duality-Invariant Field Equations For Dyons, Mustafa Emre Kansu, Murat Tanişli, Süleyman Demi̇r

Turkish Journal of Physics

The hypothetical particles dyons, which carry both electric and magnetic charges simultaneously, are widely discussed in application to electromagnetic theory and magnetohydrodynamics. Particularly, the duality-invariant field equations were suggested with suitable definitions of the dyon's electromagnetic characteristics. In this study, we propose an alternative formulation of the duality-invariant field equations for dyons based on octonion algebra. Octonions have been used to express the equations for potentials, field strengths, and sources in a more compact and consistent manner. Additionally, the octonionic form of the energy conservation law for dyons has been derived.


Reactive Wetting Of Metallic/Ceramic (Al/Α-Al2 O3 ) Systems: A Parallel Moleculardynamics Simulation Study, Gürcan Aral Jan 2020

Reactive Wetting Of Metallic/Ceramic (Al/Α-Al2 O3 ) Systems: A Parallel Moleculardynamics Simulation Study, Gürcan Aral

Turkish Journal of Physics

The reactive wetting process of a flat solid alumina (α-Al2 O3) ceramic surface by metallic aluminum (Al) nanodroplets with different shapes (spherical, cylindrical, and layer) is studied using parallel molecular dynamics (MD) simulations based on a variable charge MD method, with focuses on heat transfer, mass transfer, and the structure of the reactive region at the Al/α-Al2 O3 interface. We find that the diffusion of oxygen (O) atoms from the substrate into the droplet leads to the formation of a continuous layer of reaction product at the interface. The diffusion length of oxygen atoms into the spherical Al droplet is …


The Effect Of Temperature On Fusion Cross-Sections Of The 8b Proton Halo Nucleus, Murat Aygün Jan 2020

The Effect Of Temperature On Fusion Cross-Sections Of The 8b Proton Halo Nucleus, Murat Aygün

Turkish Journal of Physics

In the present study, I investigate the effect of temperature on fusion cross-sections of the 8B proton halo projectile. For this purpose, I evaluate two different fusion reactions, 8B + 28Si and 8B +58Ni, in the available literature. I apply two different nuclear potentials as a function of temperature. I calculate both fusion cross-sections and nuclear potentials for both reactions and I then compare the theoretical results with the experimental data. This comparison provides an opportunity for a test of different temperature-dependent potentials in explaining the fusion cross-sections with the 8B halo nucleus.


Atomic Layer Deposition Of Zirconium Oxide Thin Film On An Optical Fiber Forcladding Light Strippers, Ali̇ Karatutlu Jan 2020

Atomic Layer Deposition Of Zirconium Oxide Thin Film On An Optical Fiber Forcladding Light Strippers, Ali̇ Karatutlu

Turkish Journal of Physics

Cladding light strippers are essential components in high-power fiber lasers used for removal of unwanted cladding light that can distort the beam quality or even damage the whole fiber laser system. In this study, an Atomic Layer Deposition system was used for the first time to prepare the cladding light stripper devices using a 40 nm thick zirconia layer grown on optical fiber. The thickness of the zirconia coating was confirmed using the Scanning Electron Microscopy (SEM) and the Ellipsometry techniques. The elemental analysis was also performed using the wavelength dispersive X-ray spectroscopy technique. The Raman spectroscopy and XRD data …


Structural And Optical Properties Of Zno Films Obtained On Mesoporous Sisubstrates By The Method Of Hf Magnetron Sputtering, Valeriy Kidalov, Alena Dyadenchuk, Yuriy Bacherikov, Anton Zhuk, Tetyana Gorbaniuk, Igor Rogozin, Vitali Kidalov Jan 2020

Structural And Optical Properties Of Zno Films Obtained On Mesoporous Sisubstrates By The Method Of Hf Magnetron Sputtering, Valeriy Kidalov, Alena Dyadenchuk, Yuriy Bacherikov, Anton Zhuk, Tetyana Gorbaniuk, Igor Rogozin, Vitali Kidalov

Turkish Journal of Physics

In the present work, ZnO films were obtained on mesoporous silicon substrates by the method of HF magnetron sputtering of a metallic zinc target in reaction oxygen and argon gas medium. The properties of the ZnO films obtained on mesoporous substrates were studied depending on the ratio of the partial pressures of the working gases (argon/oxygen). X-ray analysis showed that in the process of deposition, the ZnO films of a hexagonal structure were formed. The effect of the porous layer on the structural and luminescent properties of the thin ZnO films was studied. The results showed that the porous silicon …


Magnetic Properties Of Mn Doped Crystalline And Amorphous Ge Thin Films Grown On Si (111), İlknur Gündüz Aykaç, Aykut Can Önel, Burcu Toydemi̇r Yaşasun, Leyla Çolakerol Arslan Jan 2020

Magnetic Properties Of Mn Doped Crystalline And Amorphous Ge Thin Films Grown On Si (111), İlknur Gündüz Aykaç, Aykut Can Önel, Burcu Toydemi̇r Yaşasun, Leyla Çolakerol Arslan

Turkish Journal of Physics

We investigated the effects of crystalline order on the structural and magnetic properties of ultrathin Mndoped Ge thin films grown by thermal diffusion. The dopant motion which occurs during the annealing stage appears to differ considerably depending upon whether the Ge layer is in a crystalline or an amorphous state. The details of the temperature-dependent magnetization curves reveal that the a-MnGe and c-MnGe films show ferromagnetic property up to 300K and ~250K, respectively. Ferromagnetic Mn5 Ge3 thin film with weakly anisotropic in-plane magnetization is formed on amorphous Ge thin film, while weakly ferromagnetic Mn5 Gex Si3-x nanostructures are developed on …


Anisotropic Magnetoresistance And Planar Hall Effect In Magnetoresistivenife/Pt Thin Film, Erdem Demi̇rci̇ Jan 2020

Anisotropic Magnetoresistance And Planar Hall Effect In Magnetoresistivenife/Pt Thin Film, Erdem Demi̇rci̇

Turkish Journal of Physics

The magnetoresistive NiFe/Pt sensor was fabricated by using standard microlithography and sputter deposition techniques and then the magnetic and magnetotransport properties were investigated. The magnetic properties of the sample show that the easy axis of magnetization prefers a predefined direction along the Hall bar. Moreover, the sample has uniaxial magnetic anisotropy due to the growth-induced magnetic anisotropy. On the other hand, the Anisotropic magnetoresistance (AMR) and the Planar Hall effect (PHE) of the sample were investigated in detail between 0° and 360°. The angle-dependent AMR and PHE signals at the in-plane magnetic field of constant magnitude intersect at certain angles. …


Frequency And Voltage Dependence Of Electrical Conductivity, Complex Electricmodulus, And Dielectric Properties Of Al/Alq3 /P-Si Structure, İkram Orak, Abdulkeri̇m Karabulut Jan 2020

Frequency And Voltage Dependence Of Electrical Conductivity, Complex Electricmodulus, And Dielectric Properties Of Al/Alq3 /P-Si Structure, İkram Orak, Abdulkeri̇m Karabulut

Turkish Journal of Physics

In order to enhance the capacitance of the Al/p-Si metal-semiconductor structure, the Alq3 thin film was coated between these two layers using the spin coating technique as the interlayer. The electrical conductivity, real and imaginary parts of electric modulus, dielectric loss and dielectric constant parameters were examined at the room temperature by the help of admittance measurements in the 100 kHz to 1 MHz frequency range. The effect of frequency on the dielectric constant and dielectric loss values is negligible at the negative voltage values, up to about 0.8 V, and these values rapidly ascended after 0.8 V. The function …


Four-Quark Exotic Mesons, Shahin Agaev, Kazem Azizi, Hayri̇ye Sundu Pamuk Jan 2020

Four-Quark Exotic Mesons, Shahin Agaev, Kazem Azizi, Hayri̇ye Sundu Pamuk

Turkish Journal of Physics

We review our investigations devoted to the analysis of the resonances Zc(3900), Zc(4430), Zc(4100), X(4140), X(4274), α1(1420), Y(4660), X(2100), X(2239), and Y(2175) discovered in various processes by Belle, BaBar, BESIII, D0, CDF, CMS, LHCb and COMPASS collaborations. These resonances are considered as serious candidates to four-quark (tetraquark) exotic mesons. We treat all of them as diquark-antidiquark states with relevant spin-parities, find their masses and couplings, as well as explore their dominant strong decay channels. Calculations are performed in the context of the QCD sum rule method. Thus, the spectroscopic parameters of the tetraquarks are evaluated using the two-point sum rules. …


Size-Dependent Electron Chemical Potential In Nanostructures Derived Fromstatistical Configuration, Desyana Olenka Margaretta, Nadya Amalia, Fisca Dian Utami, Riri Murniati, Sparisoma Viridi, Mikrajuddin Abdullah Jan 2020

Size-Dependent Electron Chemical Potential In Nanostructures Derived Fromstatistical Configuration, Desyana Olenka Margaretta, Nadya Amalia, Fisca Dian Utami, Riri Murniati, Sparisoma Viridi, Mikrajuddin Abdullah

Turkish Journal of Physics

We rederived the fermion distribution function by considering the effect of assembly size. We did not use Stirling approximation to avoid the deviation generated by this approximation for a small number of constituents and small assembly size. Furthermore, we identified that in small systems, the chemical potential should also depend on the assembly size. We also rederived a general expression for the size-dependent chemical potential from a statistical configuration and showed that it is consistent with the results from previously reported theoretical or simulation methods. Finally, we applied the model to derive a size-dependent thermoelectric power factor of nanostructured materials. …


Electrophysical Properties Of Pb 1-Xmnx Se Epitaxial Films Irradiatedby Γ-Quanta, Rahim Madatov, Rakshana Mamishova, Muslim Mamedov, Javanshir Ismayilov, Ulviya Faradjova Jan 2020

Electrophysical Properties Of Pb 1-Xmnx Se Epitaxial Films Irradiatedby Γ-Quanta, Rahim Madatov, Rakshana Mamishova, Muslim Mamedov, Javanshir Ismayilov, Ulviya Faradjova

Turkish Journal of Physics

Herein, the effect of γ-quanta on electrophysical and photoelectric properties of p-type Pb1-xMnx Se epitaxial films obtained from the molecular cluster on the glass substrate by the method of condensation has been investigated. It has been established that the acceptor-type local levels with the ionization energy of 0.14 eV and 0.175 eV are generated, when p-type Pb1-xMnx Se (x = 0.01) epitaxial films are irradiated by γ-quanta at D >10 kGy doses. The increase in the photoconductivity in the low temperature range 80-180K is due to the discharge of 0.14eV level, but the decrease in the rate of change of …


Prediction Of Standard Enthalpies Of Formation Of Boron Nitride Nanocones, Fahimeh Shojaie Jan 2020

Prediction Of Standard Enthalpies Of Formation Of Boron Nitride Nanocones, Fahimeh Shojaie

Turkish Journal of Physics

Prediction of the standard enthalpy of formation (ΔfH0298) of boron nitride nanocone (BNNCs) structures with disclination angles 60°, 120°, and 180°is recommended to be performed by the isodesmic reaction approach. NH3, BH3, and N2H4 were selected as key reference compounds. In order to calculate ΔfH0298 of nanocones, we must first calculate the enthalpies of nanocone rings at their apexes. For this purpose, ΔfH0298 values of 40 different structures, such as boron, nitrogen, and hydrogen compounds, have been calculated by combining Gaussian-4 (G4) theory calculations with the isodesmic and other balanced reactions approach. At each stage of the calculations, the previously …


Study Of Kno Scaling In The Emulsion Based Neutrino Experiments, Çağin Kamişcioğlu Jan 2020

Study Of Kno Scaling In The Emulsion Based Neutrino Experiments, Çağin Kamişcioğlu

Turkish Journal of Physics

KNO scaling was put forward by Koba-Nielsen-Olesen in 1972 and then tested by various experiments up to now. In this paper, the data on charged hadron multiplicity moments with KNO scaling of CHORUS and OPERA, both of them emulsion-based neutrino experiments, are compared. The results are given in detail which is very useful for tuning in MC event generators.


Generating Velocity-Dependent Potential In All Partial Waves, Ashwini Kumar Behera, Ujjwal Laha, Jhasaketan Bhoi Jan 2020

Generating Velocity-Dependent Potential In All Partial Waves, Ashwini Kumar Behera, Ujjwal Laha, Jhasaketan Bhoi

Turkish Journal of Physics

Velocity/energy-dependent potential to a parent nonlocal interaction is constructed for all partial waves by Taylor series expansion method and the related s and p-wave phase shifts for N-N and α-N systems are computed by application of modified phase equation. Our phase shifts are in good agreement with standard data.


Local Vibrational Modes Of Natural Isotopes Of Substitutional Oxygen In Cdte, Enver Tarhan, Anant K. Ramdas Jan 2020

Local Vibrational Modes Of Natural Isotopes Of Substitutional Oxygen In Cdte, Enver Tarhan, Anant K. Ramdas

Turkish Journal of Physics

We investigated the localized vibrational modes (LVM) of natural oxygen containing $^{16}$O, $^{17}$O, and $^{18}$O isotopes at a substitutional tellurium site in cadmium telluride using infrared absorption spectroscopy at cryogenic temperatures. The main absorption peak observed at 350 cm$^{-1\, }$was formerly attributed to a fundamental LVM mode ($\nu _{0})$ of oxygen at a tellurium site. The relatively weak absorption peaks observed at 331 cm$^{-1\, }$and 340 cm$^{-1\, }$are assigned as the same $\nu_{0}$ mode of the $^{17}$O and $^{18}$O isotopes, respectively, based on their relative intensities and spectral positions. The spectral positions were confirmed with theoretical calculations using a linear …


On-Chip Quantum Optics And Integrated Optomechanics, David Hoch, Timo Sommer, Sebastian Mueller, Menno Poot Jan 2020

On-Chip Quantum Optics And Integrated Optomechanics, David Hoch, Timo Sommer, Sebastian Mueller, Menno Poot

Turkish Journal of Physics

Recent developments in quantum computing and the growing interest in optomechanics and quantum optics need platforms that enable rapid prototyping and scalability. This can be fulfilled by on-chip integration, as we present here. The different nanofabrication steps are explained, and our automated measurement setup is discussed. We present an opto-electromechanical device, the H-resonator, which enables optomechanical experiments such as electrostatic springs and nonlinearities and thermomechanical squeezing. Moreover, it also functions as an optomechanical phase shifter, an essential element for our integrated quantum optics efforts. Besides this, the equivalent of a beam splitter in photonics-the directional coupler-is shown. Its coupling ratio …


Investigation Of Some Nuclear Structure Properties Of 213bi, 201ti, 188re, 186re, 133xe, 131i, 125i, 123i, 111in, 94tc, 90y, 67ga, 67cu, 62cu, 61cu, 55co, And 48v Nuclei Used In Spect In Axial Deformation, Ozan Artun Jan 2020

Investigation Of Some Nuclear Structure Properties Of 213bi, 201ti, 188re, 186re, 133xe, 131i, 125i, 123i, 111in, 94tc, 90y, 67ga, 67cu, 62cu, 61cu, 55co, And 48v Nuclei Used In Spect In Axial Deformation, Ozan Artun

Turkish Journal of Physics

The present work mainly purposed to investigate significant nuclear structure properties nuclei used in single photon emission computed tomography (SPECT), in addition to ground state nuclear properties such as the binding energy per particle, the root mean square (rms) charge, and proton and neutron radii. Besides, we calculated the neutron skin thicknesses (NST), the proton, neutron quadrupole moments ($Q_{P}, Q_{N})$, quadrupole deformation parameter ($\beta_{2})$, and the proton and neutron pairing energies ($P_{P}, P_{N})$ to determine shapes and deformations of SPECT nuclei including odd-odd or odd-even/even-odd nuclei in axial symmetry for Skyrme and Gogny interactions. To analyze the accuracy of the …


A Nonminimally Coupled, Conformally Extended Einstein-Maxwell Theory Of Pp-Waves, Dündar Teki̇n Dereli̇, Yorgo Şeni̇koğlu Jan 2020

A Nonminimally Coupled, Conformally Extended Einstein-Maxwell Theory Of Pp-Waves, Dündar Teki̇n Dereli̇, Yorgo Şeni̇koğlu

Turkish Journal of Physics

A nonminimal coupling of Weyl curvatures to electromagnetic fields is considered in Brans-Dicke-Maxwell theory. The gravitational field equations are formulated in a Riemannian spacetime where the spacetime torsion is constrained to zero by the method of Lagrange multipliers in the language of exterior differential forms. The significance and ramifications of nonminimal couplings to gravity are examined in a pp-wave spacetime.


Pseudoscalar Form Factors Of The $\Delta(1232)$ In Baryon Chiral Perturbation Theory, Yasemi̇n Ünal Jan 2020

Pseudoscalar Form Factors Of The $\Delta(1232)$ In Baryon Chiral Perturbation Theory, Yasemi̇n Ünal

Turkish Journal of Physics

The pseudoscalar current-delta transition form factors are calculated in the framework of relativistic baryon chiral perturbation theory including order $\mathcal{O}(q^4)$. The complex-mass scheme, which is suitable and well-defined for unstable particles, is taken into account as a renormalization scheme. We discuss the low energy behavior of the pseudoscalar $\tilde{g}(Q^2)$ and $\tilde{h}(Q^2)$ form factors and note that the momentum dependence of the form factors is dominated by the pion pole contributions.


Field-Free Quantum-Spin-1/2 Xxz Model In Three-Dimensions: Phases, Phase Transitions, And Phase Diagrams By Renormalization Group Theory, Ozan Sabahatti̇n Sariyer Jan 2020

Field-Free Quantum-Spin-1/2 Xxz Model In Three-Dimensions: Phases, Phase Transitions, And Phase Diagrams By Renormalization Group Theory, Ozan Sabahatti̇n Sariyer

Turkish Journal of Physics

The field-free quantum-spin-1/2 XXZ model is studied in three-dimensions using renormalization group theory. We obtain global phase diagrams and critical properties. We identify zero-temperature quantum phase transitions at isotropic points, as well as long-range order below critical temperatures at all anisotropies. We show that the excitation spectrum is gapless in XY-like, and gapped in Ising-like anisotropy regimes. Besides, internal energy density, specific heat, nearest-neighbor entanglement measures and spin-spin correlations are obtained globally at all temperatures. Our numerical results cover the global range of anisotropy parameter, for both ferromagnetic and antiferromagnetic cases.


Influence Of Annealing On Photoelectric Characteristics And Stability Of Elements Based On Si-Bi$_{2}$Te$_{3-X}$Se$_{X}$, Gurban Ahmadov Jan 2020

Influence Of Annealing On Photoelectric Characteristics And Stability Of Elements Based On Si-Bi$_{2}$Te$_{3-X}$Se$_{X}$, Gurban Ahmadov

Turkish Journal of Physics

In the manufacture of Bi$_{2}$Te$_{3-x}$Se$_{x}$-based elements using two sources of the deposited substance, they were initially annealed at a temperature of 150-200 \textdegree Ñ in a low vacuum. Heat treatment led to a slight increase in short circuit current and an increase in open circuit voltage. When the elements were heated in high vacuum, as well as in atmospheres of argon, nitrogen, hydrogen, helium and other gases, irreversible changes in the characteristics were not detected. Heat treatment of elements at a temperature of 100--150 \textdegree C in oxygen always improves their performance. It is assumed that annealing stimulates the growth …


Influence Of Capping Layer On Skyrmion And Domain-Wall Formation In Co/Pt(111), Caner Değer Jan 2020

Influence Of Capping Layer On Skyrmion And Domain-Wall Formation In Co/Pt(111), Caner Değer

Turkish Journal of Physics

In order to realize skyrmion-based next-generation logic and memory devices, investigating the impact of materialparametersonskyrmionformationisessential. Cappingmagneticthinlayersforthepurposesofbothpreventing oxidation and/or enhancing crystal structure has an influence on chiral spin texture of the layer. In this paper, we have carried out a systematic computational study on magnetic skyrmion and domain-wall formation in which 2-atomic layer of Co, deposited on Pt(111) substrate and capped by certain (Ta, Ir, and Pt) 5d elements with various thicknesses. We have determined the magnetic topography of the structures by simulations based on DFT-calculated parameters; micromagnetic Dzyaloshinskii-Moriya interaction, exchange interaction, and magnetic anisotropy coefficients. We have revealed the influence …


The Calculation Of Total Fragment Excitation Energy For Photofission Of Uranium Isotopes, Mojtaba Jamiati, Payam Mehdipour Kaldiani Jan 2020

The Calculation Of Total Fragment Excitation Energy For Photofission Of Uranium Isotopes, Mojtaba Jamiati, Payam Mehdipour Kaldiani

Turkish Journal of Physics

The total excitation energy as a function of fragment mass (TXE/A) are calculated for neutron induced fission of $^{235}$U and photofission of $^{238}$U by using the statistical model. With comparing the calculated results and the experimental data, the statistical model is modified. In new modified model, TXE are calculated by adding the neutron binding energy to the deformation energy. The calculated results using modified statistical model are in good agreement with the experimental data. Then, the total excitation energy as a function of fragment mass (TXE/A) are evaluated for photofission of Uranium isotopes.


On Current-Voltage And Capacitance-Voltage Characteristics Of Metal-Semiconductor Contacts, Abdulmeci̇t Turut Jan 2020

On Current-Voltage And Capacitance-Voltage Characteristics Of Metal-Semiconductor Contacts, Abdulmeci̇t Turut

Turkish Journal of Physics

It is expected the fact that the current following across metal-semiconductor (MS) rectifying contact named as Schottky barrier diode(SBDs)and effect of sample temperature on their electrical properties obey thermionic emission (TE) current model. But, it has been seen that the abnormal behaviors in the measured electrical characteristics cannot be exactly under stood by the classical TE transport theory. Intheliterature, the observed abnormal behaviors have been successfully explained by a Gaussian distribution function and by the pinch-off model being interaction of the neighbor patches suggested by Tung and coworkers, the named discrete regions model as "patches" with low barrier placed in …


Gup Effects On Hawking Temperature In Riemann Space-Time, Yumnam Kenedy Meitei, Telem Ibungochouba Singh, Irom Ablu Meitei Jan 2020

Gup Effects On Hawking Temperature In Riemann Space-Time, Yumnam Kenedy Meitei, Telem Ibungochouba Singh, Irom Ablu Meitei

Turkish Journal of Physics

In this paper, the modified Hawking temperature of a static Riemann space-time is studied using the generalized Klein-Gordon equation and the generalized Dirac equation. Applying the Kerner-Mann quantum tunneling method, the modified Hawking temperatures for scalar particles and fermions that cross the event horizon of the black hole have been derived. We observe that the quantum gravity effects reduce the rise of thermal radiation temperature of the black hole.


Network Dynamics Reconstruction From Data, Deni̇z Eroğlu Jan 2020

Network Dynamics Reconstruction From Data, Deni̇z Eroğlu

Turkish Journal of Physics

We consider the problem of recovering the model of a complex network of interacting dynamical units from time series of observations. We focus on typical networks which exhibit heterogeneous degrees, i.e. where the number of connections varies widely across the network, and the coupling strength for a single interaction is small. In these networks, the behavior of each unit varies according to their connectivity. Under these mild assumptions, our method provides an effective network reconstruction of the network dynamics. The method is robust to a certain size of noise and only requires relatively short time series on the state variable …


Investigating Above-Bandgap And Below-Bandgap Optical Transition In Gabias Epilayers By Photoreflectance Spectroscopy, Ömer Dönmez, Ayşe Erol Jan 2020

Investigating Above-Bandgap And Below-Bandgap Optical Transition In Gabias Epilayers By Photoreflectance Spectroscopy, Ömer Dönmez, Ayşe Erol

Turkish Journal of Physics

We present optical identification of deep level defects in as-grown and annealed GaBixAs$_{1-x}$ (x $=$ 0, 0.013 and 0.015) alloys grown at different temperatures (220 \textdegree C and 320 \textdegree C) by using photo-modulated reflectance (PR) spectroscopy and photoluminescence (PL). The PR measurements are employed at above- and below-bandgap excitations, and the PR line-shape is analyzed by the third derivative functional form (TDFF). The PR at below-bandgap excitation reveals transitions at 0.757 \textpm 0.001 eV and 0.710 \textpm 0.002 eV at 30K and 300K, respectively. Franz-Keldysh oscillations are observed in all samples under above-bandgap excitation at PR measurements, and the …


Quantum Thermodynamics And Quantum Coherence Engines, Asli Tuncer Özdemi̇r, Özgür Esat Müstecaplioğlu Jan 2020

Quantum Thermodynamics And Quantum Coherence Engines, Asli Tuncer Özdemi̇r, Özgür Esat Müstecaplioğlu

Turkish Journal of Physics

The advantages of quantum effects in several technologies, such as computation and communication, have already been well appreciated. Some devices,such as quantum computers and communication links,exhibiting superiority to their classical counterparts,have been demonstrated. The close relationship between information and energy motivates us to explore if similar quantum benefits can be found in energy technologies. Investigation of performance limits for a broader class of information-energy machines is the subject of the rapidly emerging field of quantum thermodynamics. Extension of classical thermodynamical laws to the quantum realm is far from trivial. This short review presents some of the recent efforts in this …


Unraveling Energy Consumption By Using Low-Cost And Reevaluated Thermoelectric Thin Films, Gi̇zem Durak Yüzüak, Seray Özkan, Ercüment Yüzüak Jan 2020

Unraveling Energy Consumption By Using Low-Cost And Reevaluated Thermoelectric Thin Films, Gi̇zem Durak Yüzüak, Seray Özkan, Ercüment Yüzüak

Turkish Journal of Physics

Energy is undoubtedly one of our most important demands whose consumption is constantly increasing and will continue to increase soon. One of the most important factors in attaining the required energy is to provide high efficiency at a low cost with the help of new technological improvements by evaluating wastes. Energy demand could be achieved for a relatively large thermoelectric power value by recycling the Peltier modules from waste ones and adjusting their properties with nanotechnology. For this aim, thermoelectric thin film modules were grown on silicon (Si), glass, and Kapton substrates with thermal evaporation method by using two different …