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111.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2018,130(22):6687-6691
The search of new borates with improved functional properties has attracted considerable attention. Herein, a new polar fluorooxoborate, NaB4O6F (NBF) was prepared by high‐temperature solid‐state reaction. NBF belongs to the AB4O6F family (A=alkali metal or ammonium), a series of compounds that undergoes significant cation‐dependent structural changes. NBF is of particular interest owing to the special cation position. Temperature‐dependent ionic conductivity measurements show that NBF is a solid ionic conductor, and it has the lowest active energy of 32.5 kJ mol−1 of fluorooxoborates. NBF also shows a second‐harmonic generation (SHG) response of 0.9×KH2PO4 and 0.2×β‐BaB2O4, at 1064 and 532 nm, respectively, and it has a short UV cutoff edge below 180 nm. Based on bond valence (BV) concepts, symmetry analysis, and the first principles calculation, the unique [B4O6F]∞ layer can be regarded as the “multifunctional unit”, which is responsible for the observed properties of NBF. 相似文献
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For the weakly coupled lattice
3
6
theory in a hierarchical model approximation a nonperturbative renormalization group analysis in the spirit of Gawedzki and Kupiainen is performed to study the flow of the effective actions. We deduce a domain of attraction to the tricritical (Gaussian) fixed point. The two relevant coupling constants of the problem are controlled by analytic continuation to complex domains, tracing their images under the renormalization group iterations. 相似文献
116.
V. Majerník 《Foundations of Physics Letters》1997,10(4):357-370
We propose a spacetime scheme representing the union of the real and non-real spacetime as a possible geometrical framework
for Caldirola’s idea, that the bradyonic motion can be regarded as a light-like motion in an additional extra space. The playground
of all physical processes is the union space. However, the physical processes in union space are differently projected on
the real and non-real spacetime. The waves linked with luxons in union space are projected on the real spacetime so that they
propagate here always with the velocity of light. The waves linked with bradyons in union space are projected on the non-real
spacetime so that they propagate here with the velocity of light. The wave linked with a bradyon in union space, which is
projected on the real spacetime, is here described by the Schroedinger and Dirac equations. There is proposed a symmetry which
demands that the physical world is in its law the same whether it is seen from real or non-real spacetime. We discuss some
consequences of this symmetry in the theory of elementary particles. 相似文献
117.
The Bethe strip of width m is the cartesian product $\mathbb {B}\times \lbrace 1,\ldots ,m\rbrace$, where $\mathbb {B}$ is the Bethe lattice (Cayley tree). We prove that Anderson models on the Bethe strip have “extended states” for small disorder. More precisely, we consider Anderson‐like Hamiltonians $H_\lambda =\frac{1}{2} \Delta \otimes 1 + 1 \otimes A\,+\,\lambda \mathcal {V}$ on a Bethe strip with connectivity K ≥ 2, where A is an m × m symmetric matrix, $\mathcal {V}$ is a random matrix potential, and λ is the disorder parameter. Given any closed interval $I\subset \big (\!-\!\sqrt{K}+a_{{\rm max}},\sqrt{K}+a_{\rm {min}}\big )$, where amin and amax are the smallest and largest eigenvalues of the matrix A, we prove that for λ small the random Schrödinger operator Hλ has purely absolutely continuous spectrum in I with probability one and its integrated density of states is continuously differentiable on the interval I. 相似文献
118.
Collins Okon Edet Francisco Cleiton E. Lima Carlos Alberto S. Almeida Norshamsuri Ali Muhammad Asjad 《Entropy (Basel, Switzerland)》2022,24(8)
We investigate quantum information by a theoretical measurement approach of an Aharanov–Bohm (AB) ring with Yukawa interaction in curved space with disclination. We obtained the so-called Shannon entropy through the eigenfunctions of the system. The quantum states considered come from Schrödinger theory with the AB field in the background of curved space. With this entropy, we can explore the quantum information at the position space and reciprocal space. Furthermore, we discussed how the magnetic field, the AB flux, and the topological defect influence the quantum states and the information entropy. 相似文献
119.
AbstractThe pressure dependence of the structural, elastic, electronic and thermal properties of Kondo insulator SmB6 have been systematically studied by density functional theory combined with the quasi-harmonic Debye model. The calculated structure at zero pressure is in good agreement with the available experimental results at low temperature. The obtained elastic constants, bulk modulus and shear modulus indicate that SmB6 is mechanically stable and behaves in a brittle manner under the applied pressure 0–20 GPa, consistent with available experimental data. In addition, the elastic-relevant properties, Young’s modulus and the Poisson ratio manifest that increasing pressure results in an enhancement in the stiffness of the compound. It is found that unlike temperature, pressure has little effect on the heat capacity of SmB6. What more important is that we observed an insulator to metal phase transition at about 5.5 GPa through the disappearance of the band gap, well consistent with the experimental data. This transition has little effect on the physical properties of SmB6. 相似文献
120.