Journal of Theoretical and Applied Physics (JTAP) Study of virtual annihilation and retardation effects in relativistic two-, four-, and six-body wave equations in scalar QFT Volume 11 (2017) Issue 4, November and December 2017 2023 11 17 Study of virtual annihilation and retardation effects in relativistic two-, four-, and six-body wave equations in scalar QFT 10.1007/s40094-017-0264-x EN Journal Article 2023 11 17 AbstractThe variational method within the Hamiltonian formalism of QFT using Darewych reformulated model has been used for scalar particles and antiparticles interacting through a scalar mediating field. We have investigated the relativistic effects such as virtual annihilation interactions and retardation effects for relativistic two-, four-, and six-body wave equations in scalar QFT. Approximate ground-state solutions have been studied for different strengths of coupling, for both massive and massless mediating fields where the virtual annihilation terms or retardation effects in the wave equations have been included or eliminated.

Journal of Theoretical and Applied Physics (JTAP) Two and three particles entanglement; helicity and spin with momentum Volume 11 (2017) Issue 4, November and December 2017 2023 11 17 Two and three particles entanglement; helicity and spin with momentum 10.1007/s40094-017-0265-9 EN Journal Article 2023 11 17 AbstractConstruction of the reduced spin and helicity density matrix for systems of two and three particles are described by a wave packet with sharp and Gaussian momentum distribution. The entropy for the spin and helicity part of the systems is calculated from the viewpoint of moving observers.

Journal of Theoretical and Applied Physics (JTAP) The new wave-ring helical (WRH) slow-wave structure for traveling wave tube amplifiers Volume 11 (2017) Issue 4, November and December 2017 2023 11 17 The new wave-ring helical (WRH) slow-wave structure for traveling wave tube amplifiers 10.1007/s40094-017-0266-8 EN Journal Article 2023 11 17 AbstractIn this paper, the new slow-wave structure called wave-ring helix to enhance the power of the traveling wave tubes is introduced. In this new structure, without increasing the length and radius of the helix, the wave motion path can be increased to radiofrequency wave in phase with the electron beam. The results show that in the special frequency range the output power and gain are greater than conventional helix. In this paper, optimization results are presented in cold and hot tests on the new structure. The software CST is used in S-band frequency range.

Journal of Theoretical and Applied Physics (JTAP) Proof of factorization of χcJdocumentclass[12pt]{minimal} usepackage{amsmath} usepackage{wasysym} usepackage{amsfonts} usepackage{amssymb} usepackage{amsbsy} usepackage{mathrsfs} usepackage{upgreek} setlength{oddsidemargin}{-69pt} egin{document}$$chi _{ ext{cJ}}$$end{document} production in non-equilibrium QCD at RHIC and LHC in color singlet mechanism Volume 11 (2017) Issue 4, November and December 2017 2023 11 17 Proof of factorization of χcJdocumentclass[12pt]{minimal} usepackage{amsmath} usepackage{wasysym} usepackage{amsfonts} usepackage{amssymb} usepackage{amsbsy} usepackage{mathrsfs} usepackage{upgreek} setlength{oddsidemargin}{-69pt} egin{document}$$chi _{ ext{cJ}}$$end{document} production in non-equilibrium QCD at RHIC and LHC in color singlet mechanism 10.1007/s40094-017-0267-7 EN Journal Article 2023 11 17 AbstractRecently we have proved the factorization of NRQCD S-wave heavy quarkonium production at all orders in coupling constant. In this paper we extend this to prove the factorization of infrared divergences in χcJdocumentclass[12pt]{minimal} usepackage{amsmath} usepackage{wasysym} usepackage{amsfonts} usepackage{amssymb} usepackage{amsbsy} usepackage{mathrsfs} usepackage{upgreek} setlength{oddsidemargin}{-69pt} egin{document}$$chi _{ ext{cJ}}$$end{document} production from color singlet cc¯documentclass[12pt]{minimal} usepackage{amsmath} usepackage{wasysym} usepackage{amsfonts} usepackage{amssymb} usepackage{amsbsy} usepackage{mathrsfs} usepackage{upgreek} setlength{oddsidemargin}{-69pt} egin{document}$$c{ ar{c}}$$end{document} pair in non-equilibrium QCD at RHIC and LHC at all orders in coupling constant. This can be relevant to study the quark–gluon plasma at RHIC and LHC.

Journal of Theoretical and Applied Physics (JTAP) Role of Ar/O2 mixture on structural, compositional and optical properties of thin copper oxide films deposited by DC magnetron sputtering Volume 11 (2017) Issue 4, November and December 2017 2023 11 17 Role of Ar/O2 mixture on structural, compositional and optical properties of thin copper oxide films deposited by DC magnetron sputtering 10.1007/s40094-017-0268-6 EN Journal Article 2023 11 17 AbstractIn this study, the effect of oxygen content on a thin copper oxide layer deposited on BK7 and steel substrates by DC magnetron sputtering were investigated. Argon as working gas with impurity of 99.9% and various oxygen ratios were used to sputter a pure Cu cathode target in a cylindrical geometry. The produced samples were analyzed by X-ray diffraction (XRD), energy-dispersive X-ray (EDX), atomic force microscopy (AFM), and spectrophotometry techniques. The films thickness was measured by profilometer facility. The results show that by increasing oxygen content in the working gas the sputtering rate reduces. Moreover, the type of oxide phase (Cu2O or CuO) in the synthesized layer and consequently its optical properties dramatically depend on Ar/O2 ratio in the working gas.

Journal of Theoretical and Applied Physics (JTAP) Rapid growth of zinc oxide nanobars in presence of electric field by physical vapor deposition Volume 11 (2017) Issue 4, November and December 2017 2023 11 17 Rapid growth of zinc oxide nanobars in presence of electric field by physical vapor deposition 10.1007/s40094-017-0270-z EN Journal Article 2023 11 17 AbstractIn this contribution, electric field has some effects to increase growth for specific time duration on zinc oxide (ZnO) nanobars. First, the zinc (Zn) thin film has been prepared by 235,000 V/m electric field assisted physical vapor deposition (PVD) at vacuum of 1.33 × 10−5 mbar. Second, strong electric field of 134,000 V/m has been used in ambient for growing ZnO nanobars in term of the time include 2.5 and 10 h. The performances of the ZnO nanostructure in absence and presence of electric field have been determined by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The results of XRD analysis showed that ZnO has a hexagonal bars structure and a strongly preferred (101) orientation which is strongest than without applying electric field. SEM analysis revealed that physical vapored ZnO thin film in presence of electric field are densely packed with uniform morphological, thinner and denser in distribution. Electric field effect for ZnO growth in 2.5 h is better than it in the 2.5 h without electric field but by passing the time the media influence has good power almost as same as electric field. Through this electric field in PVD, the compact and uniform Zn film has been achieved which is less diameter than ordinary PVD method. Finally, we carry out a series of experiments to grow different-orientation ZnO nanobars with less than 100 nm in diameter, which are the time saving process in base of PVD ever reported. Therefore, the significant conclusion in usage electric field is reducing time of growth.

Journal of Theoretical and Applied Physics (JTAP) A pulsed plasma jet with the various Ar/N2 mixtures Volume 11 (2017) Issue 4, November and December 2017 2023 11 17 A pulsed plasma jet with the various Ar/N2 mixtures 10.1007/s40094-017-0271-y EN Journal Article 2023 11 17 AbstractIn this paper, using the Optical Emission Spectroscopy technique, the physical properties of a fabricated pulsed DBD plasma jet are studied. Ar/N2 gaseous mixture is taken as operational gas, and Ar contribution in Ar/N2 mixture is varied from 75 to 95%. Through the optical emission spectra analysis of the pulsed DBD plasma jet, the rotational, vibrational and excitation temperatures and density of electrons in plasma medium of the pulsed plasma jet are obtained. It is seen that, at the wavelength of 750.38 nm, the radiation intensity from the Ar 4p → 4 s transition increases at the higher Ar contributions in Ar/N2 mixture. It is found that, for 95% of Ar presence in the mixture, the emission intensities from argon and molecular nitrogen are higher, and the emission line intensities will increase nonlinearly. In addition, it is observed that the quenching of Ar* by N2 results in the higher intensities of N2 excited molecules. Moreover, at the higher percentages of Ar in Ar/N2 mixture, while all the plasma temperatures are increased, the plasma electron density is reduced.

Journal of Theoretical and Applied Physics (JTAP) Effects on selective epitaxial growth of strained-SiGe p-MOSFETs on various (001) Si recess structures Volume 11 (2017) Issue 4, November and December 2017 2023 11 17 Effects on selective epitaxial growth of strained-SiGe p-MOSFETs on various (001) Si recess structures 10.1007/s40094-018-0272-5 EN Journal Article 2023 11 17 AbstractInfluences of source and drain recess structures on SiGe epitaxy growth, SiGe step height, facet formation, ID,sat and resistance performance are investigated. Growth rate of SiGe height increases with decreased recess width at a fixed depth of 62 nm. Under a fixed recess width of 96.3 nm, the deeper the recess, the higher the growth rate of SiGe height. An increase in the depth/width ratio of the recessed Si geometry may promote SiGe {001} growth. Upon the recess, SiGe step height is influenced by the initial SiGe orientation. A longer {001} facet of SiGe initial orientation causes a higher growth rate of SiGe step height. Higher IDsat and lower resistance can be achieved by increasing SiGe volume with wider recess width, deeper recess depth, and higher SiGe step height.

Journal of Theoretical and Applied Physics (JTAP) A frequency-based parameter for rapid estimation of magnitude Volume 11 (2017) Issue 4, November and December 2017 2023 11 17 A frequency-based parameter for rapid estimation of magnitude 10.1007/s40094-018-0273-4 EN Journal Article 2023 11 17 AbstractThis study introduce a new frequency parameter called τfcwtdocumentclass[12pt]{minimal} usepackage{amsmath} usepackage{wasysym} usepackage{amsfonts} usepackage{amssymb} usepackage{amsbsy} usepackage{mathrsfs} usepackage{upgreek} setlength{oddsidemargin}{-69pt} egin{document}$$ au_{ ext{fcwt}}$$end{document}, which can be used to estimate earthquake magnitude on the basis of the first few seconds of P-waves, using the waveforms of earthquakes occurring in Japan. This new parameter is introduced using continuous wavelet transform as a tool for extracting the frequency contents carried by the first few seconds of P-wave. The empirical relationship between the logarithm of τfcwtdocumentclass[12pt]{minimal} usepackage{amsmath} usepackage{wasysym} usepackage{amsfonts} usepackage{amssymb} usepackage{amsbsy} usepackage{mathrsfs} usepackage{upgreek} setlength{oddsidemargin}{-69pt} egin{document}$$ au_{ ext{fcwt}}$$end{document} within the initial 4 s of a waveform and magnitude was obtained. To evaluate the precision of τfcwtdocumentclass[12pt]{minimal} usepackage{amsmath} usepackage{wasysym} usepackage{amsfonts} usepackage{amssymb} usepackage{amsbsy} usepackage{mathrsfs} usepackage{upgreek} setlength{oddsidemargin}{-69pt} egin{document}$$ au_{ ext{fcwt}}$$end{document}, we also calculated parameters τpmaxdocumentclass[12pt]{minimal} usepackage{amsmath} usepackage{wasysym} usepackage{amsfonts} usepackage{amssymb} usepackage{amsbsy} usepackage{mathrsfs} usepackage{upgreek} setlength{oddsidemargin}{-69pt} egin{document}$$ au_{ ext{p}}^{ hbox{max} }$$end{document} and τcdocumentclass[12pt]{minimal} usepackage{amsmath} usepackage{wasysym} usepackage{amsfonts} usepackage{amssymb} usepackage{amsbsy} usepackage{mathrsfs} usepackage{upgreek} setlength{oddsidemargin}{-69pt} egin{document}$$ au_{ ext{c}}$$end{document}. The average absolute values of observed and estimated magnitude differences (|Mest-Mobs|documentclass[12pt]{minimal} usepackage{amsmath} usepackage{wasysym} usepackage{amsfonts} usepackage{amssymb} usepackage{amsbsy} usepackage{mathrsfs} usepackage{upgreek} setlength{oddsidemargin}{-69pt} egin{document}$$|M_{ ext{est}} - M_{ ext{obs}} |$$end{document}) were 0.43, 0.49, and 0.66 units of magnitude, as determined using τpmaxdocumentclass[12pt]{minimal} usepackage{amsmath} usepackage{wasysym} usepackage{amsfonts} usepackage{amssymb} usepackage{amsbsy} usepackage{mathrsfs} usepackage{upgreek} setlength{oddsidemargin}{-69pt} egin{document}$$ au_{ ext{p}}^{ hbox{max} }$$end{document}, τcdocumentclass[12pt]{minimal} usepackage{amsmath} usepackage{wasysym} usepackage{amsfonts} usepackage{amssymb} usepackage{amsbsy} usepackage{mathrsfs} usepackage{upgreek} setlength{oddsidemargin}{-69pt} egin{document}$$ au_{ ext{c}}$$end{document}, and τfcwtdocumentclass[12pt]{minimal} usepackage{amsmath} usepackage{wasysym} usepackage{amsfonts} usepackage{amssymb} usepackage{amsbsy} usepackage{mathrsfs} usepackage{upgreek} setlength{oddsidemargin}{-69pt} egin{document}$$ au_{ ext{fcwt}}$$end{document}, respectively. For earthquakes with magnitudes greater than 6, these values were 0.34, 0.56, and 0.44 units of magnitude, as derived using τpmaxdocumentclass[12pt]{minimal} usepackage{amsmath} usepackage{wasysym} usepackage{amsfonts} usepackage{amssymb} usepackage{amsbsy} usepackage{mathrsfs} usepackage{upgreek} setlength{oddsidemargin}{-69pt} egin{document}$$ au_{ ext{p}}^{ hbox{max} }$$end{document}, τcdocumentclass[12pt]{minimal} usepackage{amsmath} usepackage{wasysym} usepackage{amsfonts} usepackage{amssymb} usepackage{amsbsy} usepackage{mathrsfs} usepackage{upgreek} setlength{oddsidemargin}{-69pt} egin{document}$$ au_{ ext{c}}$$end{document}, and τfcwtdocumentclass[12pt]{minimal} usepackage{amsmath} usepackage{wasysym} usepackage{amsfonts} usepackage{amssymb} usepackage{amsbsy} usepackage{mathrsfs} usepackage{upgreek} setlength{oddsidemargin}{-69pt} egin{document}$$ au_{ ext{fcwt}}$$end{document}, respectively. The τfcwtdocumentclass[12pt]{minimal} usepackage{amsmath} usepackage{wasysym} usepackage{amsfonts} usepackage{amssymb} usepackage{amsbsy} usepackage{mathrsfs} usepackage{upgreek} setlength{oddsidemargin}{-69pt} egin{document}$$ au_{ ext{fcwt}}$$end{document} parameter exhibited more precision in determining the magnitude of moderate- and small-scale earthquakes than did the τcdocumentclass[12pt]{minimal} usepackage{amsmath} usepackage{wasysym} usepackage{amsfonts} usepackage{amssymb} usepackage{amsbsy} usepackage{mathrsfs} usepackage{upgreek} setlength{oddsidemargin}{-69pt} egin{document}$$ au_{ ext{c}}$$end{document}-based approach. For a general range of magnitudes, however, the τpmaxdocumentclass[12pt]{minimal} usepackage{amsmath} usepackage{wasysym} usepackage{amsfonts} usepackage{amssymb} usepackage{amsbsy} usepackage{mathrsfs} usepackage{upgreek} setlength{oddsidemargin}{-69pt} egin{document}$$ au_{ ext{p}}^{ hbox{max} }$$end{document}-based method showed more acceptable precision than did the other two parameters.

Journal of Theoretical and Applied Physics (JTAP) Investigation morphological, electrical, and optical properties of Mn-doped ZnO thin film by sol–gel spin-coating method Volume 11 (2017) Issue 4, November and December 2017 2023 11 17 Investigation morphological, electrical, and optical properties of Mn-doped ZnO thin film by sol–gel spin-coating method 10.1007/s40094-018-0274-3 EN Journal Article 2023 11 17 AbstractIn this study, ZnO was doped with 0.01% Mn and it is grown on p-Si by the sol–gel spin-coating method. Obtained the thin film was studied that to understand the effect of 0.01% Mn-doping ratio on the optical and electrical properties of ZnO structure. In this context, first, the morphological structure of the thin film was studied with the use of atomic force microscopy (AFM). The surface structure was obtained homogeneous, and roughness and fiber size were calculated between 27.2–33.6 and 0.595–0.673 nm, respectively. Second, the optical properties were characterized via ultraviolet–visible (UV–Vis) spectrophotometry. Third, the effect of light intensity on junction properties of the photodiode was studied. The current–voltage (I–V) of the photodiode was measured under dark and at the different intensities of illumination. Obtained results showed that the current of photodiode was increased with the intensity of illumination from 6.41 × 10−7 to 5.32 × 10−4 A. These results indicate that photocurrent under illumination is higher than the dark current. After that, the other parameters of the photodiode such as barrier height and ideality factor were determined from forwarding I–V plots using the thermionic emission model that the barrier height and the ideality factor were found 0.74 eV and 5.3, respectively. On the other hand, the capacitance–voltage (C–V) was measured at the different frequencies. The C–V characteristic shown that C–V characteristic of the photodiode was changed depends on increasing frequency. In addition, the interface density (Dit) value was decreased by increasing frequency too. Similarly, the serial resistance of the photodiode was also decreased by increasing frequency. Received all these results indicated that Mn-doped ZnO thin film sensitive to light and due to this property, it can be used for different optoelectronic applications as a photodiode and photosensor.