World Journal of Condensed Matter Physics最新文献

{"title":"Compressed H<sub>3</sub>S: Fits to the Empirical <i>H<sub>c2</sub>(T)</i> Data and a Discussion of the Meissner Effect","authors":"Gulshan Prakash Malik, Vijaya Shankar Varma","doi":"10.4236/wjcmp.2023.134008","DOIUrl":"https://doi.org/10.4236/wjcmp.2023.134008","url":null,"abstract":"Based on μ-, T- and H-dependent pairing and number equations and the premise that μ(T) is predominantly the cause of the variation of the upper critical field Hc2(T), where μ, T and H denote the chemical potential, temperature and the applied field, respectively, we provide in this paper fits to the empirical Hc2(T) data of H3S reported by Mozaffari, et al. (2019) and deal with the issue of whether or not H3S exhibits the Meissner effect. Employing a variant of the template given by Dogan and Cohen (2021), we examine in detail the results of Hirsch and Marsiglio (2022) who have claimed that H3S does not exhibit the Meissner effect and Minkov, et al. (2023) who have claimed that it does. We are thus led to suggest that monitoring the chemical potential (equivalently, the number density of Cooper pairs Ns at T = Tc) should shed new light on the issue being addressed.","PeriodicalId":308307,"journal":{"name":"World Journal of Condensed Matter Physics","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135319123","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}

{"title":"Degenerate States in Nonlinear Sigma Model with U(1) Symmetry —For Study on Violation of Cluster Property","authors":"T. Munehisa","doi":"10.4236/wjcmp.2021.113003","DOIUrl":"https://doi.org/10.4236/wjcmp.2021.113003","url":null,"abstract":"Entanglement in quantum theory is a concept that has confused many scientists. This concept implies that the cluster property, which means no relations between sufficiently separated two events, is non-trivial. In the works for some quantum spin systems, which have been recently published by the author, extensive and quantitative examinations were made about the violation of cluster property in the correlation function of the spin operator. The previous study of these quantum antiferromagnets showed that this violation is induced by the degenerate states in the systems where the continuous symmetry spontaneously breaks. Since this breaking is found in many materials such as the high temperature superconductors and the superfluidity, it is an important question whether we can observe the violation of the cluster property in them. As a step to answer this question we study a quantum nonlinear sigma model with U(1) symmetry in this paper. It is well known that this model, which has been derived as an effective model of the quantum spin systems, can also be applied to investigations of many materials. Notifying that the existence of the degenerate states is essential for the violation, we made numerical calculations in addition to theoretical arguments to find these states in the nonlinear sigma model. Then, successfully finding the degenerate states in the model, we came to a conclusion that there is a chance to observe the violation of cluster property in many materials to which the nonlinear sigma model applies.","PeriodicalId":308307,"journal":{"name":"World Journal of Condensed Matter Physics","volume":"66 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126231306","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}

{"title":"An Inquiry into Two Intriguing Values of the Critical Current Density of Bi-2212","authors":"G. P. Malik, V. S. Varma","doi":"10.4236/wjcmp.2021.113004","DOIUrl":"https://doi.org/10.4236/wjcmp.2021.113004","url":null,"abstract":"The empirically reported values of the critical current density (jc) of Bi-2212 as 2.4 × 105 (jc1; Sample 1) and 1.0 × 106 A/cm2 (jc2; Sample 2) are intriguing because both of them correspond to the same values of the temperature T = 4.2 K and the applied magnetic field H = 12 × 104 G. This difference is conventionally attributed to such factors—not all of which are quantifiable—as the geometry, dimensions and the nature of dopants and the manners of preparation of the samples which cause their granular structures, grain boundaries, alignment of the grains and so on to differ. Based on the premise that the chemical potential μ subsumes most of these features, given herein is a novel explanation of the said results in terms of the values of μ of the two samples. This paper revisits the problem that was originally addressed in [Malik G.P., Varma V.S. (2020) WJCMP, 10, 53-70] in the more accurate framework of a subsequent paper [Malik G.P., Varma V.S. (2021) JSNM, 34, 1551-1561]. Besides, it distinguishes between the contributions of the electro-electron (e-e) and the hole-hole (h-h) pairs to jc—a feature to which no heed was paid earlier. The essence of our findings is that the jcs of the two samples differ because they are characterized by different values of the primary variables μi and , where is the effective mass of a charge-carrier and me is the free-electron mass and i = 1 and 2 denote Sample 1 and Sample 2, respectively. In the scenario of the charge-carriers being predominantly h-h pairs, the values of these parameters are estimated to be: μ1 ≈ 12.3 meV, η1 ≈ 0.58; μ2 ≈ 22.7 meV, η2 ≈ 0.94. Following from these and similar estimates when the charge-carriers are e-e pairs, given below for each sample are the detailed results for the values of the secondary variables viz. the number density of the charge-carriers and their critical velocity, the number of occupied Landau levels and the magnetic interaction parameter.","PeriodicalId":308307,"journal":{"name":"World Journal of Condensed Matter Physics","volume":"302 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114385704","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}

{"title":"Phase Diagram and Edge States of Surface States of Topological Superconductors","authors":"Weihao Zhao","doi":"10.4236/wjcmp.2021.113005","DOIUrl":"https://doi.org/10.4236/wjcmp.2021.113005","url":null,"abstract":"Majorana fermions in two-dimensional systems satisfy non-Abelian statistics. They are possible to exist in topological superconductors as quasi particles, which is of great significance for topological quantum computing. In this paper, we study a new promising system of superconducting topological surface state topological insulator thin films. We also study the phase diagrams of the model by plotting the Majorana edge states and the density of states in different regions of the phase diagram. Due to the mirror symmetry of the topological surface states, the Hamiltonian can be block diagonalized into two spin-triplet p-wave superconductors, which are also confirmed by the phase diagrams. The chiral Majorana edge modes may provide a new route for realizing topological quantum computation.","PeriodicalId":308307,"journal":{"name":"World Journal of Condensed Matter Physics","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134477510","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}

{"title":"A Consistent Model of Terrestrial Planet Magnetospheres and Rotations in Our Solar System","authors":"F. Cadieu","doi":"10.4236/WJCMP.2021.112002","DOIUrl":"https://doi.org/10.4236/WJCMP.2021.112002","url":null,"abstract":"The Sun comprises 99.9% of the solar system mass so it is expected that Sun terrestrial planet interactions can influence the motion as well as the rotation of the terrestrial planets. Gravity affects the planet orbital motions while the changing magnetic fields of the Sun can influence the planet rotations. Planets that manifest a magnetic field dominate any weaker magnetic fields from the Sun, but the rotation of terrestrial planets without a magnetic field interacts with the changing Sun’s field dependent on the electrical conductivity of the core region. It is determined that the average planet density becomes a useful quantity to describe the magnetic state of a terrestrial planet. An average density of 5350 ± 50 kg/m3 is hypothesized to separate planets that develop magnetospheres from those that do not. Planets with higher average densities, Mercury and Earth, developed magnetospheres. While those with lower average densities, Venus and Mars never developed magnetospheres. Terrestrial planets with magnetospheres are the ones to also exhibit plate tectonics. The small size of Mercury led to Mercury only exhibiting a frozen in magnetization of potentially magnetic regions. The lack of magnetospheres as well as lack of plate tectonics prevented the continual transfer of core heat to the surface that limited the surface vulcanism to an initial phase. For Venus, it meant that the surface regions would only sporadically convulse. In this picture, the apparent anomalous axial rotation of Venus is a natural consequence of the rotation of the Sun. For Mars with relatively low surface temperatures, it meant that there was little heat exchange through the crust that would allow the lower crust to retain large amounts of water. For Mars to have initially had flowing liquid water required that the atmosphere at that time contained high concentrations of infrared absorbing gases at least as compared to the present level of infrared absorbing gases on the Earth. The terrestrial planets have iron based cores because iron has the highest binding energy per nucleon that can be made in the steady state lives of massive stars no matter how massive. This suggests that many of the conclusions reached here may also be applicable to exoplanets.","PeriodicalId":308307,"journal":{"name":"World Journal of Condensed Matter Physics","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131500080","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}

{"title":"Texture of Rotary-Friction-Welded from Dissimilar Medium Carbon Steels","authors":"Z. Boumerzoug, E. Priymak, A. Stepanchukova, A. Helbert, F. Brisset, T. Baudin","doi":"10.4236/wjcmp.2020.104011","DOIUrl":"https://doi.org/10.4236/wjcmp.2020.104011","url":null,"abstract":"The purpose of the present study was to investigate the texture in dissimilar medium carbon steels welded by rotary friction technique. The Electron Backscatter Diffraction (EBSD) technique was the main technique used to investigate the effect of welding on grain size and grain crystallographic orientation in the welded joint. Moreover, the effect of isothermal heat treatment at 600°C on welded joint has been studied knowing that this annealing allows to decrease the residual stresses. EBSD results revealed different subzones in welded joint. The texture in the weld is essentially composed of three components: Goss {110} , Rotated Cube {100} , and Rotated Goss {110} orientation. The heat treatments applied on welded material had a slight effect on texture and grain size.","PeriodicalId":308307,"journal":{"name":"World Journal of Condensed Matter Physics","volume":"53 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128178076","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}

{"title":"The Total Energy in the Interaction of X-Ray Photons with Capacitors","authors":"S. Hassan, G. Scarel","doi":"10.4236/wjcmp.2020.104010","DOIUrl":"https://doi.org/10.4236/wjcmp.2020.104010","url":null,"abstract":"Context and Background: In this research, we investigate the interaction of X-rays with a capacitor by studying the voltage established in the capacitor during the illumination. Motivation: We aim at verifying that the total energy conserved in the interaction is Pτ, i.e. the product of the average power P times the period τ of the X-rays. Hypothesis: Our investigation relies on the hypothesis that the voltage responsivity πV of the capacitor should be small, according to previous research. The parameter πV is the ratio between the voltage produced and the average power P of the X-rays, and measures the performance of the capacitor in response to the X-rays. Method: We measure the voltage produced by the capacitor in response to the X-rays, and then determine the average power P of the X-rays according to a procedure already assessed with infrared and visible light. Results: In our experiments, P turns out to be in the range between 10-3 W to 100 W. Our procedure enables us to unveil the relationship between the average power P and the effective dose, an important operating parameter used to measure the delivery of X-rays in practical applications, such as standard X-ray medical imaging machines. Conclusions: We believe that our procedure paves the way for designing a possible X-ray power-meter, a tool presently missing in the market of X-ray characterization tools.","PeriodicalId":308307,"journal":{"name":"World Journal of Condensed Matter Physics","volume":"105 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116851703","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}

{"title":"Fabrication of Polymer Magnetic Nanocomposites Containing Carbon Nanoparticles Doped with Cobalt Nanoclusters and Study Their Conductivity, Self-Healing and Adhesion Properties","authors":"G. Маmniashvili, D. Gventsadze, L. Rukhadze, L. Maisuradze","doi":"10.4236/wjcmp.2020.103008","DOIUrl":"https://doi.org/10.4236/wjcmp.2020.103008","url":null,"abstract":"The technology of fabrication of polymer \u0000nanocomposites on basis of carbon nanoparticles doped with cobalt clusters, \u0000synthesized by original Chemical Vapore Deposition (CVD) technology developed \u0000by authors, was elaborated. Carbon shells provide both the protection of ferromagnetic \u0000impurities from aggressive environment and new unique properties to the hybride \u0000nanostructures. The self-assembling of magnetic clusters coated by carbon \u0000shells presents just such example which could be used in the contemporary \u0000materials, for example, in strong magnets, analytic instruments (nuclear \u0000magnetic resonance tomographs) and nanosensors. Their good conductivity, \u0000self-healing and adhesion properties were demonstrated by applying the combined \u0000action of temperature, pressure, steady and alternating magnetic fields to \u0000stimulate diffusion of magnetic nanoparticles in direction to defect sites. Due \u0000to these properties fabricated magnetic polymer nanocomposites could have \u0000perspective for potential.","PeriodicalId":308307,"journal":{"name":"World Journal of Condensed Matter Physics","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131402586","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}

{"title":"Estimation of the Power of the Anomalous Microwave Emission","authors":"Kristopher T. Pickens, G. Scarel","doi":"10.4236/wjcmp.2020.103007","DOIUrl":"https://doi.org/10.4236/wjcmp.2020.103007","url":null,"abstract":"Context \u0000and Background: The product of the electromagnetic (EM) wave’s \u0000power P times its period τ, i.e. Pτ, is the amount of energy conserved \u0000in EM wave’s absorption in matter. Whether Pτ is the amount of energy conserved in the emission of EM waves from matter is \u0000not assessed. Motivation: In this research, \u0000we perform a computational study to explore the ability of Pτ to represent the \u0000amount of energy conserved in EM wave’s emission from matter. Hypothesis: Since the magnitude of the power P of \u0000emitted EM waves computed through Larmor’s formula for a rotating dipole is \u0000excessively small, we alternatively hypothesize that Pτ and the law of conservation of energy can lead to a realistic \u0000estimation of P. Methods: We \u0000estimate the power PAME of \u0000the anomalous microwave emission (AME), a well-characterized radiation \u0000generated in the interstellar medium (ISM) by spinning dust grains, and one possible source of contamination of the cosmic \u0000microwave background (CMB). For our estimation of PAME, we assume the AME to be generated in a molecular \u0000cloud mostly populated by spinning silicate nanoparticles (SSNs) or polycyclic \u0000aromatic hydrocarbon (PAH) spinning dust grains. Indeed, SSNs and PAHs are \u0000listed among the most probable sources of AME, and their characteristics are \u0000well-known. We discriminate between realistic and non-realistic values of PAME based upon the magnitude \u0000of two parameters that depend on PAME: \u0000the significant distance z, and the \u0000time of photon production T. The \u0000parameter z is the space interval from the spinning dust grain within which the \u0000spinning dust grain’s electric field is effective. Results: Using the \u0000information available for AME, SSNs and PAHs, we estimate the power PAME using both Larmor’s \u0000formula and Pτ. We compare and \u0000comment the results obtained for z and T. Conclusions: Our study \u0000highlights the effectiveness of Pτ over \u0000Larmor’s formula in providing a realistic value of PAME. This finding might have consequences in quantum \u0000technology of single photon detection and production.","PeriodicalId":308307,"journal":{"name":"World Journal of Condensed Matter Physics","volume":"104 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130045075","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}

{"title":"Phase Transitions Governed by the Fifth Power of the Golden Mean and Beyond","authors":"H. Otto","doi":"10.4236/wjcmp.2020.103009","DOIUrl":"https://doi.org/10.4236/wjcmp.2020.103009","url":null,"abstract":"In this contribution results from different disciplines of science were compared \u0000to show their intimate interweaving with each other having in common the golden \u0000ratio φ respectively its fifth power φ5. The research fields cover \u0000model calculations of statistical physics associated with phase transitions, the \u0000quantum probability of two particles, new physics of everything suggested by the \u0000information relativity theory (IRT) including \u0000explanations of cosmological relevance, the e-infinity \u0000theory, superconductivity, and the Tammes problem of the largest diameter of N non-overlapping \u0000circles on the surface of a sphere with its connection to viral morphology and crystallography. \u0000Finally, Fibonacci anyons proposed for topological \u0000quantum computation (TQC) were \u0000briefly described in comparison to the recently formulated reverse Fibonacci approach using the Janicko number sequence. An architecture applicable for a quantum computer is proposed \u0000consisting of 13-step twisted microtubules similar to tubulin microtubules of living \u0000matter. Most topics point to the omnipresence of the golden mean as the numerical \u0000dominator of our world.","PeriodicalId":308307,"journal":{"name":"World Journal of Condensed Matter Physics","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130934439","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}