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Full-Text Articles in Physical Sciences and Mathematics

Design Of A Multifunctional Sample Probe For Transport Measurements, Mustafa Öztürk, Numan Akdoğan Jan 2018

Design Of A Multifunctional Sample Probe For Transport Measurements, Mustafa Öztürk, Numan Akdoğan

Turkish Journal of Physics

Herein, we describe a multifunctional sample probe equipped with a two-axis goniometer for transport measurements. The two-axis goniometer enables both computer-controlled 360$^{\circ}$ out-of-plane and manual 360$^{\circ}$ in-plane rotations. The multifunctional sample probe was successfully implemented to a host dewar and an electromagnet system. The developed probe is capable of performing transport measurements while fully controlling the parameters such as the magnetic and electrical fields, the angle, the temperature, and the current/voltage parameters in a wide range. The design of the multifunctional sample probe allows easy installation into different dewar and magnet systems and connection of a wide range of external …


Super Inflation Mechanism And Dark Energy From A Cosmological Entropy Perspective, Ali̇ İhsan Keski̇n Jan 2018

Super Inflation Mechanism And Dark Energy From A Cosmological Entropy Perspective, Ali̇ İhsan Keski̇n

Turkish Journal of Physics

Various approaches are developed that provide a unification of the early inflationary epoch of the universe and dark energy (cosmic accelerating expansion case). In one respect, we express this unification in a universal thermodynamic framework within the context of $F\left( T,T_{G} \right)$ gravity, where $T$ represents the torsion invariant and $T_{G}$ is the teleparallel equivalent of the Gauss--Bonnet term. For a Friedmann-Robertson-Walker universe model bounded by the dynamical apparent horizon, we explore the generalized second law of gravitational thermodynamics (GSLT). Finally, we discuss the super inflation mechanism, the deceleration case (radiation and dust regions), and the late time cosmic acceleration …


Permanent Magnet Motion In A Copper Tube, Jaroslav Franek, Martin Soka Jan 2018

Permanent Magnet Motion In A Copper Tube, Jaroslav Franek, Martin Soka

Turkish Journal of Physics

This paper deals with the investigation of braking forces induced by eddy currents, which have effects on the permanent magnet moving at a constant speed in the direction of the conductive tube axis. The analysis is based on calculation of an action of a force between the current density, representing the magnet, and the eddy currents. The chosen solution is based on classical electrodynamics and can serve as a guide for the calculation of other cases, where braking forces are created between the moving cell, which is a source of the magnetic field, and a close conductive subject. The obtained …


The Influence Of Deposit Composition Controlled By Changing The Relative Fe Ion Concentration On Properties Of Electroplated Nanocrystalline Co-Fe-Cu Ternary Thin Films, Umut Saraç, Mali̇k Kaya, Mevlana Celaletti̇n Baykul Jan 2018

The Influence Of Deposit Composition Controlled By Changing The Relative Fe Ion Concentration On Properties Of Electroplated Nanocrystalline Co-Fe-Cu Ternary Thin Films, Umut Saraç, Mali̇k Kaya, Mevlana Celaletti̇n Baykul

Turkish Journal of Physics

Ternary Co-Fe-Cu thin films with 78.5-92.4 at.% Co, 4.1-17.9 at.% Fe, and 3.1-3.6 at.% Cu were electroplated at ambient temperature from electrolytes with different relative Fe ion concentrations with respect to the Co ion concentration on the glass substrates coated with indium tin oxide (ITO). It was revealed that the Fe is more easily deposited than Co for all electrolyte conditions. The phase structure of the films changed from a mixture of hcp Co and fcc/hcp Co to a mixture of fcc/hcp Co and bcc Fe and the mean crystallite size diminished with increasing Fe content within the deposits. A …


Control Of Laser-Induced Nonadiabatic Molecular Alignment In Dissipative Media, Gamze Kaya Jan 2018

Control Of Laser-Induced Nonadiabatic Molecular Alignment In Dissipative Media, Gamze Kaya

Turkish Journal of Physics

Laser-induced nonadiabatic alignment in nitrogen and mixtures of nitrogen with Ar gas was investigated using the ultrafast optical Kerr effect in the collinear pump-probe setup. We find that dissipative media produce desired alignment characteristics in distinct manners to decoherence and to population relaxation. The results show that the intense laser alignment can be used as a control tool of molecular dynamics in dissipative environments.


Theory And Application Of Hydrogen Formation In Proton-Alkali Atom Collision, Sabbah Abdelwahab Elkilany Jan 2018

Theory And Application Of Hydrogen Formation In Proton-Alkali Atom Collision, Sabbah Abdelwahab Elkilany

Turkish Journal of Physics

The possibility of producing more hydrogen during p-alkali atom collisions is discussed. The coupled static approximation is modified for the first time to make it applicable to the multichannel problem of the collisions of p-alkali atoms. The formation of H (1s) and excited H (in 2s- and 2p- states) in the scattering of p-Li atoms is treated to test the convergence of our method. The modified method is used to calculate the total cross-sections of seven partial waves in a range of energy between 50 and 1000 keV. Our p-Li results are compared with earlier ones.


Photon In A Cylindrical Resonant Cavity, Cavi̇t Teki̇nçay, Yusuf Sucu Jan 2018

Photon In A Cylindrical Resonant Cavity, Cavi̇t Teki̇nçay, Yusuf Sucu

Turkish Journal of Physics

In this study, the massless and massive spin-1 particle equations, derived from the excited states of the zitterbewegung model, are considered for the photon in the cylindrical resonant cavity background. The resonant frequencies of the particles are also obtained. We show that these frequencies become equivalent in the $M^{2}\to 0$ limit.


Quantum Many-Body Interactions In The Presence Of Disordered Potentials, Riza Oğul Jan 2018

Quantum Many-Body Interactions In The Presence Of Disordered Potentials, Riza Oğul

Turkish Journal of Physics

The time evolution of the quantum nonequilibrium states of many-body particles is described with a set of hierarchies of quantum kinetic equations with quantum wave functions. A collision term is obtained in terms of two-body interactions in the mean-field with a disordered potential, which is proposed for the first time. The implications and the limits of applicability of the resulting kinetic equations are discussed.


Thermodynamics Of Cosmological Models With Generalized $G$ And $\Lambda $, M Saratchandra Singh, Sanasam Surendra Singh Jan 2018

Thermodynamics Of Cosmological Models With Generalized $G$ And $\Lambda $, M Saratchandra Singh, Sanasam Surendra Singh

Turkish Journal of Physics

Here we investigate spatially flat Friedmann-Robertson-Walker space-time models of the universe to study the thermodynamic behaviors in light of variables $G$ and $\Lambda $. A particular method to find the solutions of Einstein's field equations and mathematical expressions for temperature and entropy of the perfect fluid cosmological models is introduced by using both the equation of state and the assumption $G=G_{0} \,a^{n}$. It is observed that the phantom field of ($\omega


Spectral Properties Of The Galactic Supernova Remnant Vela Jr. (G266.2-1.2) Using Chandra, Nergi̇s Cesur, Aytap Sezer, Murat Hüdaverdi̇ Jan 2018

Spectral Properties Of The Galactic Supernova Remnant Vela Jr. (G266.2-1.2) Using Chandra, Nergi̇s Cesur, Aytap Sezer, Murat Hüdaverdi̇

Turkish Journal of Physics

An X-ray nonthermal spectral investigation of the galactic shell-type supernova remnant (SNR) Vela Jr. using archival data from Chandra for the northern and northwestern rims of the SNR is presented. Spectra were extracted from four emission regions in these rims (three in the northwestern rim and one in the northern). The X-ray spectra of the northwestern rim were well reproduced by a single power-law and the synchrotron model srcut, and for the north rim, the spectra were fitted by a single and a broken power-law, respectively. The spectra of both rims show no line emission. Each spectrum was fit by …


Monte Carlo Simulation Of Dynamic Phase Transition Properties Of Core-Shell Magnetic Nanoparticles With Similar Volumes, Erol Vatansever Jan 2018

Monte Carlo Simulation Of Dynamic Phase Transition Properties Of Core-Shell Magnetic Nanoparticles With Similar Volumes, Erol Vatansever

Turkish Journal of Physics

We implement Monte Carlo simulations to determine dynamic phase transition features of both cubical and spherical nanoparticles composed of spin-1/2 cores surrounded by a spin-1 shell layer. The particles are subjected to an oscillating magnetic field. We plan these particles such that they have similar volumes. It is observed that the nonequilibrium magnetic phase transition temperatures of the particles with similar volumes explicitly depend on their geometrical shapes as well as the system parameters. The cubic one has a higher transition temperature than the spherical one for the small interface coupling, whereas the transition temperature of the spherical particle becomes …


A Minimal Fermion-Scalar Preonic Model, Ümi̇t Kaya, Bi̇lgehan Bariş Öner, Saleh Sultanov Jan 2018

A Minimal Fermion-Scalar Preonic Model, Ümi̇t Kaya, Bi̇lgehan Bariş Öner, Saleh Sultanov

Turkish Journal of Physics

A minimal fermion-scalar preonic model containing two fermionic preons and one scalar preon is proposed. This scheme allows prevention of the occurrence of undesired SM-level particles, namely leptons and quarks with unusual electric charges. Similar to the previous FS models, color-octet leptons and color-sextet quarks, which are expected to have masses much lower than the compositeness scale, are predicted. Observation of these particles could provide first indications of preonic models. The FCC/SppC pp option will give an opportunity to probe $m_{q_{6}}$ up to 48/75 TeV and $m_{l_{8}}$ up to 15/27 TeV within 1 year of operation at nominal luminosity. FCC/SppC …


Galactic H$\Alpha $ Emission Line Studies Using Defpos At The Tübi̇tak National Observatory, Muhi̇tti̇n Şahan Jan 2018

Galactic H$\Alpha $ Emission Line Studies Using Defpos At The Tübi̇tak National Observatory, Muhi̇tti̇n Şahan

Turkish Journal of Physics

H$\alpha $ spectral line (6563 Å) profiles of eight northern H II regions in our galaxy (Sh2-25, Sh2-131, Sh2-237, IC 434, IC 1318, NGC 1982, NGC 6543, and NGC 6611) have been obtained using the Dual Etalon Fabry-Pérot Optical spectrometer (DEFPOS) with a 4' field of view, located at the coudé focus of the 150 cm RTT150 telescope at the TÜBİTAK National Observatory (TUG, Antalya, Turkey). Observations were carried out during the nights of 25-27 December 2015 and 6-7 June 2017 with different long exposure times ranging from 900 s to 3600 s. These spectra provide information about the local …


Structural And Permeability Characterization Of Zn-Li Ferrites, M H Mesbah Ahmed, A. K. M. Akther Hossain, Shamima Choudhury Jan 2018

Structural And Permeability Characterization Of Zn-Li Ferrites, M H Mesbah Ahmed, A. K. M. Akther Hossain, Shamima Choudhury

Turkish Journal of Physics

Structural characterization and magnetic properties of Zn-substituted Li ferrites with composition \linebreak Zn$_{x}$Li$_{0.45-x/2}$Fe$_{2.55-x/2}$O$_{4}$ (where x = 0.0, 0.1, 0.2, 0.3, 0.4, and 0.5) were studied by varying sintering temperature T$_{S}$ (where T$_{S}$ = 1000, 1050, 1100, 1150, 1200, and 1250 $^{\circ}$C) of the six samples. The single-phase cubic spinel structure was found by XRD patterns and scanning electron microscopy revealed the microstructure of all the samples. Permeability (real, $\mu_{i}'$ and imaginary, $\mu _{i}'')$ was found to increase with Zn substitution and also with sintering temperature. The real part of initial permeability ($\mu_{i}')$ was found to depend on the density and …


Solar Flare And Geomagnetic Activity Relations, Volkan Sarp, Ali̇ Kilçik Jan 2018

Solar Flare And Geomagnetic Activity Relations, Volkan Sarp, Ali̇ Kilçik

Turkish Journal of Physics

Two x-ray solar flare parameters (number of flares and peak flux) are compared to geomagnetic and space weather activity indices. The first solar flare parameter, X-ray solar flare number (SFN), is the total number of solar flares observed in a given month. The second one is the monthly maximum of X-ray solar flare peak fluxes (SFP). In order to compare these two parameters, both of them are cross-correlated with some other indices of geomagnetic activity (aa, Dst, and AE indices) and space weather (maximum coronal mass ejection speed index and solar wind speed). Maximum correlation was found ($\sim $0.63) between …


Function Mining For The $$-N$_{Ch}$ Correlations In Pp And Pp(Bar) Collisions Based On Symbolic Regression, Elsayed Eldahshan Jan 2018

Function Mining For The $$-N$_{Ch}$ Correlations In Pp And Pp(Bar) Collisions Based On Symbolic Regression, Elsayed Eldahshan

Turkish Journal of Physics

The investigation and analysis of the correlation between the mean transverse momentum () of charged particles and the charged particle multiplicity ($N_{ch}$) allow physicists to understand the contribution of multiple-parton interactions to the particle production mechanism. A symbolic regression (SR) method, based on gene expression programming (GEP), is proposed for mining a function that describes the -$N_{ch}$ correlation in proton-proton and proton-antiproton (pp and pp(bar)) collisions at collision energies from IRS to LHC. The discovered function simulates and models the correlation between and $N_{ch}$ in wide energy range $s^{1/2}$. In the framework of the proposed GEP model for $-N_{ch}$ correlation, …


Revealing The True Nature Of The Multiple System V822 Aql, Hi̇cran Bakiş Jan 2018

Revealing The True Nature Of The Multiple System V822 Aql, Hi̇cran Bakiş

Turkish Journal of Physics

Given the brightness, the V822 Aql multiple star system is photometric and spectroscopically neglected. In this study high-resolution echelle spectra of the system were obtained and were used to calculate the mass ratio of the system by determining the individual lines of the components for the first time. According to this, the close binary consists of two components revolving in a circular orbit with velocity semiamplitudes of K$_{1}$ = 45.5 $\pm $ 0.8 km/s and K$_{2}$ = 204.9 $\pm $ 0.9 km/s (q = 0.22 $\pm $ 0.01), respectively. In addition, the orbital period analysis showed a highly eccentric orbit …


Modeling And Simulation Of Czts-Perovskite Sandwiched Tandem Solar Cell, Ismaila Taiwo Bello, Mojoyinola Kofoworola Awodele, Oluwaseun Adedokun, Olusola Akinrinola, Ayodeji Oladiran Awodugba Jan 2018

Modeling And Simulation Of Czts-Perovskite Sandwiched Tandem Solar Cell, Ismaila Taiwo Bello, Mojoyinola Kofoworola Awodele, Oluwaseun Adedokun, Olusola Akinrinola, Ayodeji Oladiran Awodugba

Turkish Journal of Physics

In this research work, a solar cell capacitance simulator (SCAPS-1D) was used in the modeling and simulation of sandwiched perovskite solar cells (PSCSs) with a planar heterojunction structure in the arrangement of the sandwiched model (FTO/ZnO/CZTS/PSCS/CZTS/HTM). Two different configurations, 121 and 111, of the sandwiching absorber layer of the device were simulated and compared with the perovskite without sandwiching, using an absorber layer of step length thickness of 25 nm, and varied from 100 nm to 500 nm. The band gap diagram, I-V characteristics curve, and other parameters were constructed. The best configuration for better performance was then determined, from …


The Application Of Some Nuclear Potentials For Quasielastic Scattering Data Of The $^{11}$Li $+ ~ ^{28}$Si Reaction And Its Consequences, Murat Aygün Jan 2018

The Application Of Some Nuclear Potentials For Quasielastic Scattering Data Of The $^{11}$Li $+ ~ ^{28}$Si Reaction And Its Consequences, Murat Aygün

Turkish Journal of Physics

The aim of the present study is to provide a better understanding of the effect and applicability of nuclear potentials on scattering reactions. For this, we investigate the quasielastic scattering data of the $^{11}$Li $+ ~ ^{28}$Si reaction at 319 MeV within the framework of the optical model. In order to obtain the real part of the optical potential, we use ten different potentials, which consist of Proximity 1977 (Prox 77), Proximity 1988 (Prox 88), Broglia and Winther 1991 (BW 91), Aage Winther (AW 95), Christensen and Winther 1976 (CW 76), Bass 1973 (Bass 73), Bass 1977 (Bass 77), Bass …


Cosmic Censorship And The Third Law Of Black Hole Dynamics, Koray Düztaş Jan 2018

Cosmic Censorship And The Third Law Of Black Hole Dynamics, Koray Düztaş

Turkish Journal of Physics

Israel's proof of the third law of black hole dynamics is based on the semirigidity assumption, which requires that the areas of the outermost trapped surfaces are preserved. We argue that the condition that the area of the event horizon should not decrease is necessary -but not sufficient- for the semirigidity assumption to hold. It is known that the presence of a naked singularity in the exterior region invalidates Hawking's proof of the area theorem. In this sense, the third law assumes the validity of the strong form of the cosmic censorship conjecture, contrary to general acceptance. Still, one cannot …


Tailoring The Magnetic Anisotropy Of Cobalt-Gold Thin Films, Cengi̇z Okay, Peri̇han Aksu, Caner Deger, Fi̇kret Yildiz Jan 2018

Tailoring The Magnetic Anisotropy Of Cobalt-Gold Thin Films, Cengi̇z Okay, Peri̇han Aksu, Caner Deger, Fi̇kret Yildiz

Turkish Journal of Physics

Magnetic cobalt-gold thin films (Co$_{x}$Au$_{(1-x)})$ are grown on silicon (100) surfaces by using a sputter deposition technique. Magnetic anisotropy of the films is investigated by ferromagnetic resonance (FMR). Magnetic properties are explored by micromagnetic simulations based on the metropolis algorithm. Effective magnetic anisotropy is gradually increased with Co concentration. In-plane axial anisotropy exists for all samples and it is enhanced with a Co concentration of $\sim $40{\%}, corresponding optimal cluster size, and intercluster separation. Segregation and coalescence of Co clusters caused by different Co concentrations strongly affect magnetic properties of the thin films. Therefore, the study revealed that magnetic behavior …


Analytical Solutions Of Conformable Time, Space, And Time-Space Fractional Kdv Equations, Hasi̇be Hale Karayer, Ahmet Doğan Demi̇rhan, Fevzi̇ Büyükkiliç Jan 2018

Analytical Solutions Of Conformable Time, Space, And Time-Space Fractional Kdv Equations, Hasi̇be Hale Karayer, Ahmet Doğan Demi̇rhan, Fevzi̇ Büyükkiliç

Turkish Journal of Physics

In this study, we consider the Korteweg-de Vries (KdV) equation for solitary waves in the domain of conformable fractional calculus. By means of this fractional theory, we obtain exact solutions for time, space, and time-space fractional KdV equations and demonstrate our results graphically according to the fractional order of the related equations. Furthermore, we report that the fractional order in the solution of the time fractional KdV equation is associated with viscosity of the medium by comparing three-dimensional picture presentations of solutions of time fractional KdV and Burgers-KdV equations.


Single Production Of The Excited Muons At The Sppc-Based Ultimate Μp Collider, Abdullati̇f Çalişkan Jan 2018

Single Production Of The Excited Muons At The Sppc-Based Ultimate Μp Collider, Abdullati̇f Çalişkan

Turkish Journal of Physics

Single production potential of the excited muons at the SPPC-based ultimate muon-proton collider with center-of-mass energy of 116.6 TeV was analyzed. We calculated the production cross-sections and the decay widths of the excited muons with the process of µp → µ*X → γµX. We obtained the normalized transverse momentum and pseudorapidity distributions of the final-state particles to attain the kinematical cuts for the discovery of the excited muons. With these cuts, we determined the mass limits. It was shown that the discovery limits on the mass of the excited muons are 19.6 and 10.1 TeV for λ = mµ* and …


Silicon Nitride As Antireflection Coating To Enhance The Conversion Efficiency Of Silicon Solar Cells, Rajinder Sharma Jan 2018

Silicon Nitride As Antireflection Coating To Enhance The Conversion Efficiency Of Silicon Solar Cells, Rajinder Sharma

Turkish Journal of Physics

The aim of this work is to investigate the effect of single and double layer antireflection coating (ARC) on the performance of silicon solar cells. In this regard, various previous works on single and double layer ARCs have been consulted. Silicon nitride (Si3N4) has been used as ARC material because of its varying refractive index (1.8-3.0). Numerical calculations have been performed to obtain the reflectance for single and double layer Si3N4 using the transfer matrix method. Double layer antireflection coating (DLARC) of Si3N4 is found to have significant advantages over single layer antireflection coating (SLARC). Calculated reflectances have been further …


Analysis Of Quantum-Dot-Embedded Multicavity Arrays For On-Chip Wdm Applications, Havva Erdi̇nç, Serdar Kocaman Jan 2018

Analysis Of Quantum-Dot-Embedded Multicavity Arrays For On-Chip Wdm Applications, Havva Erdi̇nç, Serdar Kocaman

Turkish Journal of Physics

Transmission and group delay characteristics of a single-quantum-dot-(QD)-embedded double-cavity array and a triple-cavity array are compared theoretically in the weak coupling regime. When the extrinsic cavity decay rate is comparably higher than the intrinsic cavity decay rate at equal coupling strengths and normalized detuning values, transmission values of both systems converge with each other but the phase delay generated at triple-cavity systems is higher than that of the single-QD-embedded double-cavity array system. The results confirmed by the transmission calculations for both cases provide a comparative tool for designing on chip wavelength division multiplexing systems.


An Experimental Study On The Angular Dependence Of Coherent To Compton Scattering Differential Cross-Section Ratios Of Calcium, Tuba Akkuş Jan 2018

An Experimental Study On The Angular Dependence Of Coherent To Compton Scattering Differential Cross-Section Ratios Of Calcium, Tuba Akkuş

Turkish Journal of Physics

The coherent to Compton scattering cross-section ratio of calcium was measured experimentally for several polar scattering angles (90°, 100°, 110°, 120°, and 130°) and azimuthal scattering angles (30°, 20°, 10°, 0°, -10°, and -20°). A high purity germanium semiconductor detector with a resolution of 199.6 eV at 5.9 keV was used. The theoretical values of the coherent to Compton scattering differential cross-section of calcium were calculated on the basis of nonrelativistic form factors, relativistic form factors, and S-matrix theories. It was observed that the experimental results were most compatible with the nonrelativistic form factor theory.


Noether Symmetry Analysis Of Anisotropic Universe In F(T;B) Gravity, Yusuf Küçükakça Jan 2018

Noether Symmetry Analysis Of Anisotropic Universe In F(T;B) Gravity, Yusuf Küçükakça

Turkish Journal of Physics

The purpose of the present work was to investigate the Noether symmetries of the locally rotationally symmetric Bianchi type I space time in f(T;B) gravity theory, which depends on the torsion scalar T and the boundary term B. In this theory, we consider some particular models and investigate their Noether symmetry generators. Besides, we get exact cosmological solutions of the considered models including the matter dominant universe using the Noether symmetry technique. The obtained results coincide with the accelerated expansion behavior of the universe.


Information-Theoretic Measure Of The Hyperbolical Exponential-Type Potential, Atachegbe Clement Onate, Olukayode Adebimpe, Babatunde Olufemi Adebesin, Adewale Folaranmi Lukman Jan 2018

Information-Theoretic Measure Of The Hyperbolical Exponential-Type Potential, Atachegbe Clement Onate, Olukayode Adebimpe, Babatunde Olufemi Adebesin, Adewale Folaranmi Lukman

Turkish Journal of Physics

The approximate analytical solution of the 3-dimensional radial Schrödinger equation in the framework of the parametric Nikiforov-Uvarov method was obtained with a hyperbolical exponential-type potential. The energy eigenvalue equation and the corresponding wave function have been obtained explicitly. Using the integral method, we calculated Shannon entropy, information energy, Fisher information, and complexity measure. It was deduced that the complexity measure calculated using Shannon entropy with information energy and that calculated using Shannon entropy with Fisher information were similar.


Mapping Heavy Elements In The Supernova Remnant G290.1-0.8, Murat Hüdaverdi̇ Jan 2018

Mapping Heavy Elements In The Supernova Remnant G290.1-0.8, Murat Hüdaverdi̇

Turkish Journal of Physics

We present the imaging and spectroscopic study results of G290.1-0.8 Supernova Remnant (SNR) using the Suzaku X-ray archival data. The SNR belongs to the mixed-morphology class with its centrally peaked asymmetric X-ray core and distorted radio shell-like plasma. The X-ray spectra is well defined with isothermal plasma of kTe ∼ 0:5 keV. The radial profile shows enhanced elemental abundances. The EW maps reveal inhomogeneous asymmetric spatial distribution of elemental abundances. The northeast of the SNR is bright in Ne, Mg, and Si. The EW maps are enhanced in the direction of the X-ray elongation, suggesting that the distorted X-ray structure …


Electrochemical Capacitance-Voltage Profiling Of Nonuniformly Doped Gaas Heterostructures With Sqws And Mqws For Led Applications, George Yakovlev, Vasily Zubkov, Anna Solomnikova, Oleg Derevianko Jan 2018

Electrochemical Capacitance-Voltage Profiling Of Nonuniformly Doped Gaas Heterostructures With Sqws And Mqws For Led Applications, George Yakovlev, Vasily Zubkov, Anna Solomnikova, Oleg Derevianko

Turkish Journal of Physics

Light-emitting heterostructures with single and multiple GaAs/InGaAs quantum wells have been investigated by means of electrochemical capacitance-voltage (ECV) profiling. Capacitance-voltage characteristics were measured; concentration profiles of free charge carriers over the heterostructure depth as well as the intensity of quantum well filling by charge carriers were obtained. In heterostructures with a single quantum well (QW), we considered limitations of capacitance techniques for undoped QW profiling, which are situated near the metallurgic border of the p-n junction. We made a detailed consideration of phenomena related to Debye smearing and we developed and analyzed the dependence of the space charge region width …