A theory of superconductivity based on Bose-Einstein statistics was proposed,which can lead to a formula for T(critical temperature)similar to that of BCS theory,and provide a possible explanation for the complexity o...A theory of superconductivity based on Bose-Einstein statistics was proposed,which can lead to a formula for T(critical temperature)similar to that of BCS theory,and provide a possible explanation for the complexity of isotope effect and the normal state energy gap in copper-oxides.We proceeded from a 3-dimensional harmonic oscillator model to equivalent the superconducting state to a two-dimensional Bose-Einstein condensate bound longitudinally,and pointed out the application conditions of the theory.Under this scheme,we analyzed some typical structural features in copper oxides that favor the production of high-temperature superconductivity.We also discovered that combining this theory with an alternative mechanism-strong coupling to local spin configurations-provided some useful hints for exploring new superconducting materials.In addition,we pointed out a possible link between the phenomenon of superconductivity and magnetostriction,then we proposed some combinations of elements as possible candidates for high temperature superconducting materials based on those analysis.展开更多
Within the framework of quantum statistical mechanics,we have proposed an exact analytical solution to the problemof Bose-Einstein condensation(BEC)of harmonically trapped two-dimensional(2D)ideal photons.We utilize t...Within the framework of quantum statistical mechanics,we have proposed an exact analytical solution to the problemof Bose-Einstein condensation(BEC)of harmonically trapped two-dimensional(2D)ideal photons.We utilize this analyticalsolution to investigate the statistical properties of ideal photons in a 2D dye-filled spherical cap cavity.The resultsof numerical calculation of the analytical solution agree completely with the foregoing experimental results in the BEC ofharmonically trapped 2D ideal photons.The analytical expressions of the critical temperature and the condensate fractionare derived in the thermodynamic limit.It is found that the 2D critical photon number is larger than the one-dimensional(1D)critical photon number by two orders of magnitude.The spectral radiance of a 2D spherical cap cavity has a sharppeak at the frequency of the cavity cutoff when the photon number exceeds the critical value determined by a temperature.展开更多
A number of diverse kinds of magnetic experiments are shown to lead to the observation of a Bose-Einstein condensation of magnons in some nanostructures, especially in Fe and in Co/Pt. The experiments include 1) the m...A number of diverse kinds of magnetic experiments are shown to lead to the observation of a Bose-Einstein condensation of magnons in some nanostructures, especially in Fe and in Co/Pt. The experiments include 1) the measurement of magnetic aftereffect, 2) measurements of Néel’s fluctuation field, including an estimate of activation volume, 3) the measurement of the energy gap which provides a lower limit on the BEC temperature, 4) using Lagrange multipliers in the quantum thermodynamics of magnons, and 5) the observation of a visible anomaly in the Bloch T3/2 law for the temperature dependence of magnetization of nanostructured ferromagnets.展开更多
Supersymmetry (SUSY) emerged within particle physics as a means to relate two fun dame ntally different classes of elementary particles: bosons (integer spin, Bose-Einstein statistics) and fermi on sfhalfintegerspin, ...Supersymmetry (SUSY) emerged within particle physics as a means to relate two fun dame ntally different classes of elementary particles: bosons (integer spin, Bose-Einstein statistics) and fermi on sfhalfintegerspin, Fermi-Dirac statistics). Exte nsions to the Standard Model have also been proposed based on SUSY theory in order to resolve Iong-standing issues in quantum field theory, including the nature of vacuum energy, origin of mass scales and dark matter. Even though the experimental validation of SUSY is still an ongoing issue, supersymmetric/ isospectral techniques have already found applications in low-energy physics, nonrelativistic quantum mechanics, and nonlinear dynamics, to name a few. On the other hand, waveguide laser arrays have been a subject of intense investigations for the purpose of building high-power phaselocked lasers, which are immune to the detrimental effects of nonlinearities orfilamentation. Nevertheless, such systems suffer from multimode operation, which in turn leads to a chaotic emission.展开更多
文摘A theory of superconductivity based on Bose-Einstein statistics was proposed,which can lead to a formula for T(critical temperature)similar to that of BCS theory,and provide a possible explanation for the complexity of isotope effect and the normal state energy gap in copper-oxides.We proceeded from a 3-dimensional harmonic oscillator model to equivalent the superconducting state to a two-dimensional Bose-Einstein condensate bound longitudinally,and pointed out the application conditions of the theory.Under this scheme,we analyzed some typical structural features in copper oxides that favor the production of high-temperature superconductivity.We also discovered that combining this theory with an alternative mechanism-strong coupling to local spin configurations-provided some useful hints for exploring new superconducting materials.In addition,we pointed out a possible link between the phenomenon of superconductivity and magnetostriction,then we proposed some combinations of elements as possible candidates for high temperature superconducting materials based on those analysis.
基金supported by the National Natural Science Foundation of China(Grant Nos.10174024 and 10474025).
文摘Within the framework of quantum statistical mechanics,we have proposed an exact analytical solution to the problemof Bose-Einstein condensation(BEC)of harmonically trapped two-dimensional(2D)ideal photons.We utilize this analyticalsolution to investigate the statistical properties of ideal photons in a 2D dye-filled spherical cap cavity.The resultsof numerical calculation of the analytical solution agree completely with the foregoing experimental results in the BEC ofharmonically trapped 2D ideal photons.The analytical expressions of the critical temperature and the condensate fractionare derived in the thermodynamic limit.It is found that the 2D critical photon number is larger than the one-dimensional(1D)critical photon number by two orders of magnitude.The spectral radiance of a 2D spherical cap cavity has a sharppeak at the frequency of the cavity cutoff when the photon number exceeds the critical value determined by a temperature.
文摘A number of diverse kinds of magnetic experiments are shown to lead to the observation of a Bose-Einstein condensation of magnons in some nanostructures, especially in Fe and in Co/Pt. The experiments include 1) the measurement of magnetic aftereffect, 2) measurements of Néel’s fluctuation field, including an estimate of activation volume, 3) the measurement of the energy gap which provides a lower limit on the BEC temperature, 4) using Lagrange multipliers in the quantum thermodynamics of magnons, and 5) the observation of a visible anomaly in the Bloch T3/2 law for the temperature dependence of magnetization of nanostructured ferromagnets.
文摘Supersymmetry (SUSY) emerged within particle physics as a means to relate two fun dame ntally different classes of elementary particles: bosons (integer spin, Bose-Einstein statistics) and fermi on sfhalfintegerspin, Fermi-Dirac statistics). Exte nsions to the Standard Model have also been proposed based on SUSY theory in order to resolve Iong-standing issues in quantum field theory, including the nature of vacuum energy, origin of mass scales and dark matter. Even though the experimental validation of SUSY is still an ongoing issue, supersymmetric/ isospectral techniques have already found applications in low-energy physics, nonrelativistic quantum mechanics, and nonlinear dynamics, to name a few. On the other hand, waveguide laser arrays have been a subject of intense investigations for the purpose of building high-power phaselocked lasers, which are immune to the detrimental effects of nonlinearities orfilamentation. Nevertheless, such systems suffer from multimode operation, which in turn leads to a chaotic emission.
