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971.
In the present work, the electronic and optical properties of anisotropic parabolic quantum disks are studied in the presence of an applied magnetic field. For this goal, we first obtain the electron energy levels of an anisotropic parabolic quantum disk under axial, tilted, and in-plane magnetic fields. According to the results obtained for the energy levels reveal that there is no degeneracy at zero magnetic field due to symmetry breaking. With increasing the anisotropy, the energy level spacing increases. At a constant anisotropy, the energy levels splitting decreases with increasing tilt angle of magnetic field. The total refractive index changes decrease when the tilt angle of magnetic field and the anisotropy increase. Also, the total absorption coefficients increase as the tilt angle of magnetic field and anisotropy increase.  相似文献   
972.
A finite type-I superlattice with different dielectric media on either side of the surfaces is considered under a perturbing electric fields parallel to the superlattice axis on the basis of an infinite square potential well. Using the random-phase approximation, the density–density correlation function including intra- and inter-level transitions in a multiple-quantum-well (MQW) is calculated. The dispersion relations for the surface and the bulk states are obtained as functions of the momentum wave vector and the averaged electric field strength over the quantum well. The Raman intensities due to the bulk and the surface plasmons for the intra- and the inter-level transitions are also obtained for incoming light energy.  相似文献   
973.
在最弱受约束电子势模型理论框架下计算了W I原子的 , 和 系列里德堡能级,结果与实验值符合较好,最大相对误差均在2.72408E-6之内,达到了很高的精度.  相似文献   
974.
《Optimization》2012,61(2):283-289
An inventory system with unit demand, varying ordering levels and random lead times is considered in this paper. Ordering level is determined by the number of demands during last lead time. The ordering quantity will be such as to bring back the inventory level to S at the ordering epoch. No backlog is permitted. The time dependent probability distribution of the inventory level is obtained. Correlation between the number of demands during a lead time and the length of the next inventory dry period is obtained and it is illustrated by an example.  相似文献   
975.
高志福  彭秋和  王娜  邹志刚 《中国物理 B》2012,21(5):57109-057109
Once the energies of electrons near the Fermi surface obviously exceed the threshold energy of the inverse β decay,electron capture(EC) dominates inside the magnetar.Since the maximal binding energy of the 3 P 2 neutron Cooper pair is only about 0.048 MeV,the outgoing high-energy neutrons(E k(n) > 60 MeV) created by the EC can easily destroy the 3 P 2 neutron Cooper pairs through the interaction of nuclear force.In the anisotropic neutron superfluid,each 3 P 2 neutron Cooper pair has magnetic energy 2μ n B in the applied magnetic field B,where μ n = 0.966 × 10 23 erg.G 1 is the absolute value of the neutron abnormal magnetic moment.While being destroyed by the high-energy EC neutrons,the magnetic moments of the 3 P 2 Cooper pairs are no longer arranged in the paramagnetic direction,and the magnetic energy is released.This released energy can be transformed into thermal energy.Only a small fraction of the generated thermal energy is transported from the interior to the surface by conduction,and then it is radiated in the form of thermal photons from the surface.After highly efficient modulation within the star’s magnetosphere,the thermal surface emission is shaped into a spectrum of soft X-rays/γ-rays with the observed characteristics of magnetars.By introducing related parameters,we calculate the theoretical luminosities of magnetars.The calculation results agree well with the observed parameters of magnetars.  相似文献   
976.
董嫣然  张树东  侯圣伟  程起元 《中国物理 B》2012,21(8):83104-083104
Potential energy curves(PECs) for the ground state(X 2 Σ +) and the four excited electronic states(A 2 Π,B 2 Π,C 2 Σ +,4 Π) of a BeH molecule are calculated using the multi-configuration reference single and double excited configuration interaction(MRCI) approach in combination with the aug-cc-pVTZ basis sets.The calculation covers the internuclear distance ranging from 0.07 nm to 0.70 nm,and the equilibrium bond length R e and the vertical excited energy T e are determined directly.It is evident that the X2Σ+,A2Π,B2Π,C2Σ+ states are bound and 4Π is a repulsive excited state.With the potentials,all of the vibrational levels and inertial rotation constants are predicted when the rotational quantum number J is set to be equal to zero(J = 0) by numerically solving the radial Schr¨odinger equation of nuclear motion.Then the spectroscopic data are obtained including the rotation coupling constant ω e,the anharmonic constant ωexe,the equilibrium rotation constant Be,and the vibration-rotation coupling constant αe.These values are compared with the theoretical and experimental results currently available,showing that they are in agreement with each other.  相似文献   
977.
Absorption spectra of HDO/D2O mixtures recorded in the 5600-8800 cm−1 region with a total pressure of water from 13 up to 18 hPa and an absorption path length of 600 m have been analyzed in order to obtain new spectroscopic data for HD18O and D218O. In spite of the low natural 18O concentration (about 2×10−3 with respect to the 16O one), about 1100 transitions belonging to HD18O and more than 280 transitions belonging to D218O have been assigned. Most of the D218O transitions belong to the ν1+ν2+ν3 and 2ν1+ν3 bands. Sets of energy levels for seven vibrational states of D218O and four states of HD18O are reported for the first time. The comparison of the experimental data with the calculated values based on Partridge-Schwenke global variational calculations is discussed.  相似文献   
978.
We discover an error in the quantum circuit in Fig. 2 in the original paper [Y.G. Yang, Q.Y. Wen. Opt. Commun. 283 (2010) 3198-3201]. Corrected results are obtained and presented in this paper.  相似文献   
979.
Isomeric two-quasiparticle states have been identified in the neutron-rich isotopes 172Er and 174Er using multi-nucleon transfer reactions with 136Xe beams incident on various targets, and γ  -ray spectroscopy with Gammasphere. A candidate for the Kπ=6+Kπ=6+ two-quasineutron state in 172Er is found at 1500 keV. In 174Er, a nuclide whose level scheme was previously unknown, a long-lived isomer is identified at 1112 keV decaying via an inhibited E1 transition and revealing the yrast sequence of 174Er. This isomer is proposed to be a Kπ=8Kπ=8 two-quasineutron state, defining a sequence in the N=106N=106 isotones extending from the well-deformed neutron-rich isotope 174Er to the neutron-deficient isotope 188Pb, where the presence of the isomer signifies a prolate minimum in an otherwise spherical well. Configuration-constrained potential-energy surface calculations are used to predict the excitation energies of the 6+ and 8 intrinsic states and as a basis for extracting the pairing force strength, GnGn, in the N=104N=104 and N=106N=106 isotones.  相似文献   
980.
Microwave induced resistance oscillations (MIROs) were studied experimentally over a very wide range of frequencies ranging from 20 GHz up to 4 THz, and from the quasi-classical regime to the quantum Hall effect regime. At low frequencies regular MIROs were observed, with a periodicity determined by the ratio of the microwave to cyclotron frequencies. For frequencies below 150 GHz the magnetic field dependence of MIROs waveform is well described by a simplified version of an existing theoretical model, where the damping is controlled by the width of the Landau levels. In the THz frequency range MIROs vanish and only pronounced resistance changes are observed at the cyclotron resonance. The evolution of MIROs with frequency is presented and discussed.  相似文献   
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