Pub Date : 2015-04-04DOI: 10.2478/s11534-013-0266-5
E. Baskin, A. Iomin
Electrodynamics of composite materials with fractal geometry is studied in the framework of fractional calculus. This consideration establishes a link between fractal geometry of the media and fractional integrodifferentiation. The photoconductivity in the vicinity of the electrode-electrolyte fractal interface is studied. The methods of fractional calculus are employed to obtain an analytical expression for the giant local enhancement of the optical electric field inside the fractal composite structure at the condition of the surface plasmon excitation. This approach makes it possible to explain experimental data on photoconductivity in the nano-electrochemistry.
{"title":"Electro-chemical manifestation of nanoplasmonics in fractal media","authors":"E. Baskin, A. Iomin","doi":"10.2478/s11534-013-0266-5","DOIUrl":"https://doi.org/10.2478/s11534-013-0266-5","url":null,"abstract":"Electrodynamics of composite materials with fractal geometry is studied in the framework of fractional calculus. This consideration establishes a link between fractal geometry of the media and fractional integrodifferentiation. The photoconductivity in the vicinity of the electrode-electrolyte fractal interface is studied. The methods of fractional calculus are employed to obtain an analytical expression for the giant local enhancement of the optical electric field inside the fractal composite structure at the condition of the surface plasmon excitation. This approach makes it possible to explain experimental data on photoconductivity in the nano-electrochemistry.","PeriodicalId":50985,"journal":{"name":"Central European Journal of Physics","volume":"4 1","pages":"676-684"},"PeriodicalIF":0.0,"publicationDate":"2015-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79535206","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-10-01DOI: 10.2478/s11534-014-0484-5
V. Tichý, L. Skála, R. Hudec
This paper presents a direct algebraic method of searching for analytic solutions of the two-dimensional time-independent Schrödinger equation that is impossible to separate into two one-dimensional ones. As examples, two-dimensional polynomial and Morse-like potentials are discussed. Analytic formulas for the ground state wave functions and the corresponding energies are presented. These results cannot be obtained by another known method.
{"title":"Algebraic approach to non-separable two-dimensional Schrödinger equation: Ground states for polynomial and Morse-like potentials","authors":"V. Tichý, L. Skála, R. Hudec","doi":"10.2478/s11534-014-0484-5","DOIUrl":"https://doi.org/10.2478/s11534-014-0484-5","url":null,"abstract":"This paper presents a direct algebraic method of searching for analytic solutions of the two-dimensional time-independent Schrödinger equation that is impossible to separate into two one-dimensional ones. As examples, two-dimensional polynomial and Morse-like potentials are discussed. Analytic formulas for the ground state wave functions and the corresponding energies are presented. These results cannot be obtained by another known method.","PeriodicalId":50985,"journal":{"name":"Central European Journal of Physics","volume":"1 1","pages":"730-736"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82042095","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-08-27DOI: 10.2478/s11534-014-0517-0
Qiongtao Xie
We present exact analytical results for bright and dark solitons in a type of one-dimensional spatially inhomogeneous nonlinearity. We show that the competition between a homogeneous self-defocusing (SDF) nonlinearity and a localized self-focusing (SF) nonlinearity supports stable fundamental bright solitons. For a specific choice of the nonlinear parameters, exact analytical solutions for fundamental bright solitons have been obtained. By applying both variational approximation and Vakhitov-Kolokolov stability criterion, it is found that exact fundamental bright solitons are stable. Our analytical results are also confirmed numerically. Additionally, we show that a homogeneous SF nonlinearity modulated by a localized SF nonlinearity allows the existence of exact dark solitons, for certain special cases of nonlinear parameters. By making use of linear stability analysis and direct numerical simulation, it is found that these exact dark solitons are linearly unstable.
{"title":"Exact solutions for bright and dark solitons in spatially inhomogeneous nonlinearity","authors":"Qiongtao Xie","doi":"10.2478/s11534-014-0517-0","DOIUrl":"https://doi.org/10.2478/s11534-014-0517-0","url":null,"abstract":"We present exact analytical results for bright and dark solitons in a type of one-dimensional spatially inhomogeneous nonlinearity. We show that the competition between a homogeneous self-defocusing (SDF) nonlinearity and a localized self-focusing (SF) nonlinearity supports stable fundamental bright solitons. For a specific choice of the nonlinear parameters, exact analytical solutions for fundamental bright solitons have been obtained. By applying both variational approximation and Vakhitov-Kolokolov stability criterion, it is found that exact fundamental bright solitons are stable. Our analytical results are also confirmed numerically. Additionally, we show that a homogeneous SF nonlinearity modulated by a localized SF nonlinearity allows the existence of exact dark solitons, for certain special cases of nonlinear parameters. By making use of linear stability analysis and direct numerical simulation, it is found that these exact dark solitons are linearly unstable.","PeriodicalId":50985,"journal":{"name":"Central European Journal of Physics","volume":"5 1","pages":"830-835"},"PeriodicalIF":0.0,"publicationDate":"2014-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79514848","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-08-27DOI: 10.2478/s11534-014-0522-3
R. Haq, S Nadeem, Z. H. Khan, T. G. Okedayo
Current study examines the magnetohydrodynamic (MHD) boundary layer flow of a Casson nanofluid over an exponentially permeable shrinking sheet with convective boundary condition. Moreover, we have considered the suction/injection effects on the wall. By applying the appropriate transformations, system of non-linear partial differential equation along with the boundary conditions are transformed to couple non-linear ordinary differential equations. The resulting systems of non-linear ordinary differential equations are solved numerically using Runge-Kutta method. Numerical results for velocity, temperature and nanoparticle volume concentration are presented through graphs for various values of dimensionless parameters. Effects of parameters for heat transfer at wall and nanoparticle volume concentration are also presented through graphs and tables. At the end, fluid flow behavior is examined through stream lines. Concluding remarks are provided for the whole analysis.
{"title":"Convective heat transfer and MHD effects on Casson nanofluid flow over a shrinking sheet","authors":"R. Haq, S Nadeem, Z. H. Khan, T. G. Okedayo","doi":"10.2478/s11534-014-0522-3","DOIUrl":"https://doi.org/10.2478/s11534-014-0522-3","url":null,"abstract":"Current study examines the magnetohydrodynamic (MHD) boundary layer flow of a Casson nanofluid over an exponentially permeable shrinking sheet with convective boundary condition. Moreover, we have considered the suction/injection effects on the wall. By applying the appropriate transformations, system of non-linear partial differential equation along with the boundary conditions are transformed to couple non-linear ordinary differential equations. The resulting systems of non-linear ordinary differential equations are solved numerically using Runge-Kutta method. Numerical results for velocity, temperature and nanoparticle volume concentration are presented through graphs for various values of dimensionless parameters. Effects of parameters for heat transfer at wall and nanoparticle volume concentration are also presented through graphs and tables. At the end, fluid flow behavior is examined through stream lines. Concluding remarks are provided for the whole analysis.","PeriodicalId":50985,"journal":{"name":"Central European Journal of Physics","volume":"44 1","pages":"862-871"},"PeriodicalIF":0.0,"publicationDate":"2014-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87034932","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-08-27DOI: 10.2478/s11534-014-0520-5
Xin Yang, D. Yan, Qian-qian Bao, Yan Zhang, Cui-Li Cui
Owing to interference induced by spontaneous emission, the density-matrix equations in a three-level Λ-type system have an additional coherence term, which plays a critical role in modulating the inversionless gain and electromagnetically induced transparency effect. In addition, it is shown that spontaneously generated coherence (SGC) has an effect on the entanglement between an atom and a photon of the coupling laser field by calculating the degree of entanglement (DEM) of the atomic system. In this paper, we investigate the influence of the SGC effect on atom-photon entanglement in a Λ-type system, which generally remains a high entangled state. When an incoherent pump source is introduced, we find that the SGC effect could exert considerable influence on the atom reduced entropy under certain conditions for both transient and steady states. More interestingly, such an incoherent pump field could actively affect the short-time dynamic behaviors of the transient quantum entangled state at a certain range of pump rate as a typical coherent case.
{"title":"The influence of spontaneously generated coherence on atom-photon entanglement in a Λ-type system with an incoherent pump","authors":"Xin Yang, D. Yan, Qian-qian Bao, Yan Zhang, Cui-Li Cui","doi":"10.2478/s11534-014-0520-5","DOIUrl":"https://doi.org/10.2478/s11534-014-0520-5","url":null,"abstract":"Owing to interference induced by spontaneous emission, the density-matrix equations in a three-level Λ-type system have an additional coherence term, which plays a critical role in modulating the inversionless gain and electromagnetically induced transparency effect. In addition, it is shown that spontaneously generated coherence (SGC) has an effect on the entanglement between an atom and a photon of the coupling laser field by calculating the degree of entanglement (DEM) of the atomic system. In this paper, we investigate the influence of the SGC effect on atom-photon entanglement in a Λ-type system, which generally remains a high entangled state. When an incoherent pump source is introduced, we find that the SGC effect could exert considerable influence on the atom reduced entropy under certain conditions for both transient and steady states. More interestingly, such an incoherent pump field could actively affect the short-time dynamic behaviors of the transient quantum entangled state at a certain range of pump rate as a typical coherent case.","PeriodicalId":50985,"journal":{"name":"Central European Journal of Physics","volume":"11 1","pages":"813-821"},"PeriodicalIF":0.0,"publicationDate":"2014-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88414194","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-08-27DOI: 10.2478/s11534-014-0512-5
M. Musztyfaga-Staszuk, L. Dobrzański
The paper presents the results of the investigation of the front contact manufactured using silver pastes (based on experimentally prepared silver powder) on monocrystalline silicon solar cells in order to reduce contact resistance. Various deposition and fabrication techniques were applied to improve the electrical properties of contacts. The aim of the paper was to apply an unconventional method (selective laser sintering) to improve the quality of forming contacts of silicon solar cells. The topography of both the melted/sintered contact and textured silicon was investigated using atomic force microscopy. Resistance of front electrodes was measured using the Transmission Line Model (TLM). Both surface topography and cross section of front contacts were researched using the scanning electron microscopy.
{"title":"The use of laser technology to shape properties of the contacts of silicon solar cells and their structure","authors":"M. Musztyfaga-Staszuk, L. Dobrzański","doi":"10.2478/s11534-014-0512-5","DOIUrl":"https://doi.org/10.2478/s11534-014-0512-5","url":null,"abstract":"The paper presents the results of the investigation of the front contact manufactured using silver pastes (based on experimentally prepared silver powder) on monocrystalline silicon solar cells in order to reduce contact resistance. Various deposition and fabrication techniques were applied to improve the electrical properties of contacts. The aim of the paper was to apply an unconventional method (selective laser sintering) to improve the quality of forming contacts of silicon solar cells. The topography of both the melted/sintered contact and textured silicon was investigated using atomic force microscopy. Resistance of front electrodes was measured using the Transmission Line Model (TLM). Both surface topography and cross section of front contacts were researched using the scanning electron microscopy.","PeriodicalId":50985,"journal":{"name":"Central European Journal of Physics","volume":"86 1","pages":"836-842"},"PeriodicalIF":0.0,"publicationDate":"2014-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83704768","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-08-27DOI: 10.2478/s11534-014-0519-y
H. Yakut, E. Tabar, A. Kuliev, E. Guliyev
In this paper the Quasiparticle-Phonon Nuclear Model (QPNM), based on QRPA (Quasiparticle Random Phase Approximation) phonons, has been utilized to investigate spin polarization effects on the groundstate magnetic properties such as intrinsic magnetic moment (gK) and effective spin gyromagnetic factor (gseff.) of odd-mass deformed 165–179Hf isotopes with K > 1/2. Investigations of the spin polarization effects of the even core on the magnetic moments show that the spin gyromagnetic factors (gs) of the nucleons in the nucleus differ noticeably from the corresponding values for free nucleons and that the spin-spin interactions play an important role in the re-normalization of gs factors of the odd-mass 165–179Hf isotopes. In addition, some theoretical predictions are presented for the magnetic moments of 165Hf, 167Hf, and 169Hf, whose ground state magnetic moments haven’t been experimentally determined yet.
{"title":"The ground-state magnetic moments of odd-mass Hf isotopes","authors":"H. Yakut, E. Tabar, A. Kuliev, E. Guliyev","doi":"10.2478/s11534-014-0519-y","DOIUrl":"https://doi.org/10.2478/s11534-014-0519-y","url":null,"abstract":"In this paper the Quasiparticle-Phonon Nuclear Model (QPNM), based on QRPA (Quasiparticle Random Phase Approximation) phonons, has been utilized to investigate spin polarization effects on the groundstate magnetic properties such as intrinsic magnetic moment (gK) and effective spin gyromagnetic factor (gseff.) of odd-mass deformed 165–179Hf isotopes with K > 1/2. Investigations of the spin polarization effects of the even core on the magnetic moments show that the spin gyromagnetic factors (gs) of the nucleons in the nucleus differ noticeably from the corresponding values for free nucleons and that the spin-spin interactions play an important role in the re-normalization of gs factors of the odd-mass 165–179Hf isotopes. In addition, some theoretical predictions are presented for the magnetic moments of 165Hf, 167Hf, and 169Hf, whose ground state magnetic moments haven’t been experimentally determined yet.","PeriodicalId":50985,"journal":{"name":"Central European Journal of Physics","volume":"52 1","pages":"843-850"},"PeriodicalIF":0.0,"publicationDate":"2014-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80036895","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-08-27DOI: 10.2478/s11534-014-0521-4
S. Ortakaya
The pseudospin and spin symmetric solutions of the Dirac equation with Hulthén-type tensor interaction are obtained under multi-parameter-exponential potential (MEP) for arbitrary κ states. The energy eigenvalues and the corresponding eigenfunctions are also obtained using the parametric Nikiforov-Uvarov (NU) method. Some numerical results are also obtained for pseudospin and spin symmetry limits.
{"title":"Dirac equation with multiparameter-potential and Hulthén tensor interaction under relativistic symmetries","authors":"S. Ortakaya","doi":"10.2478/s11534-014-0521-4","DOIUrl":"https://doi.org/10.2478/s11534-014-0521-4","url":null,"abstract":"The pseudospin and spin symmetric solutions of the Dirac equation with Hulthén-type tensor interaction are obtained under multi-parameter-exponential potential (MEP) for arbitrary κ states. The energy eigenvalues and the corresponding eigenfunctions are also obtained using the parametric Nikiforov-Uvarov (NU) method. Some numerical results are also obtained for pseudospin and spin symmetry limits.","PeriodicalId":50985,"journal":{"name":"Central European Journal of Physics","volume":"19 1","pages":"822-829"},"PeriodicalIF":0.0,"publicationDate":"2014-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84976293","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-08-17DOI: 10.2478/s11534-014-0513-4
A. E. Çalık
In the present work, the matrix elements, isospin impurities and log ft values of the isospin forbidden 0+ → 0+ beta decays have been investigated. The calculated results have been compared with available experimental and another theoretical data. The isotopic invariance of the Hamiltonian has been restored by Pyatov method. Within the quasi-particle random phase approximation (QRPA), the computations have been performed both in presence and absence of the pairing interactions.
{"title":"Investigation of isospin forbidden 0+ → 0+ Fermi beta decays with Pyatov method","authors":"A. E. Çalık","doi":"10.2478/s11534-014-0513-4","DOIUrl":"https://doi.org/10.2478/s11534-014-0513-4","url":null,"abstract":"In the present work, the matrix elements, isospin impurities and log ft values of the isospin forbidden 0+ → 0+ beta decays have been investigated. The calculated results have been compared with available experimental and another theoretical data. The isotopic invariance of the Hamiltonian has been restored by Pyatov method. Within the quasi-particle random phase approximation (QRPA), the computations have been performed both in presence and absence of the pairing interactions.","PeriodicalId":50985,"journal":{"name":"Central European Journal of Physics","volume":"174 1","pages":"785-791"},"PeriodicalIF":0.0,"publicationDate":"2014-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76926153","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-08-17DOI: 10.2478/s11534-014-0516-1
K. Eshwarappa, Kiggal Udayashankar Kiran, K. Ravindraswami, H. Somashekarappa
Saturation thickness for multiple scattering gamma rays from multiple sources has been measured experimentally and simulated using the Monte Carlo N-Particle (MCNP) Code. Experimental measurements were performed using a collimated beam of gamma-rays from 57Co, 203Hg, 133Ba, 22Na, 137Cs, 65Zn and 60Co sources. The gamma rays were directed at rectangular aluminium targets of varying thickness. A NaI (Tl) scintillation detector placed at a backscattering angle of 180° was used to detect the scattered photons. The measured and calculated saturation thickness increases with increasing energy of incident gamma-rays. Experimental and simulated values are compared and are in good agreement.
{"title":"Experimental and simulated validation of the energy dependence of saturation thickness of multiple scattered gamma rays","authors":"K. Eshwarappa, Kiggal Udayashankar Kiran, K. Ravindraswami, H. Somashekarappa","doi":"10.2478/s11534-014-0516-1","DOIUrl":"https://doi.org/10.2478/s11534-014-0516-1","url":null,"abstract":"Saturation thickness for multiple scattering gamma rays from multiple sources has been measured experimentally and simulated using the Monte Carlo N-Particle (MCNP) Code. Experimental measurements were performed using a collimated beam of gamma-rays from 57Co, 203Hg, 133Ba, 22Na, 137Cs, 65Zn and 60Co sources. The gamma rays were directed at rectangular aluminium targets of varying thickness. A NaI (Tl) scintillation detector placed at a backscattering angle of 180° was used to detect the scattered photons. The measured and calculated saturation thickness increases with increasing energy of incident gamma-rays. Experimental and simulated values are compared and are in good agreement.","PeriodicalId":50985,"journal":{"name":"Central European Journal of Physics","volume":"24 1","pages":"792-798"},"PeriodicalIF":0.0,"publicationDate":"2014-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82489025","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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