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991.
Far-infrared reflectivity spectra of Cu2S have been measured from 20 to 700 cm−1 at several temperatures through the superionic transition temperature Tc. Many bands and two broad bands were observed at low and high temperatures, respectively. From the spectra, we determined optical dielectric constant ∞, the angular frequencies of longitudinal (LO) and transverse (TO) optical phonons, and transverse effective charge. Based on these values, we suggest significant role of small band gap for high ionic conduction with small activation energy and the possibility of lattice distortion arising from an enhanced effective charge. Anomalous temperature dependence has been found for ∞ and TO–LO splitting. 相似文献
992.
The effects of polarons along main chain and spin-soliton-like along side-radical lattice in doped quasi-one-dimensional π-conjugated organic ferromagnets are studied by selfconsistent method. It is shown that the gap of spin-down and spin-up mid energy bands of the system decreases because new energy levels of localization states appear. The stability of organic ferromagnetic system is weakened with decreasing of the gap. In addition, it is also shown that there is charge transfer between main chain and side-radical lattice of the doped system. 相似文献
993.
In the cases with and without a perturbation possessing the S0sdg(5) (or SUsdg(5)) symmetry in the supersymmetry scheme with many-body interactions, superdeformed bands in the odd-A Lu isotopes 163,165,167Lu are investigated. Quantitatively good results of γ-ray energies and dynamical moments of inertia are obtained in both of the two cases. It shows that the supersymmetry scheme with many-body interactions has almost the same power to describe the triaxial superdeformed bands as to the other superdeformed bands. 相似文献
994.
A theoretical investigation of 1D stationary and transient quasi-periodical dielectric structures is presented. A new approach for solving the problem of field interaction with such structures common for both stationary and transient cases, based on integral equations for the fields in transient media, is proposed. Some special cases of quasi-periodical structures with doubled quasi-periodicity are investigated numerically, showing that an additional complexity of the structure allows to obtain good filtering properties with a small number of quasi-periods. Transient structures with the same spatial dependencies, but with a time-dependent permittivity were also investigated. 相似文献
995.
N. G. Basov G. D. Hager A. A. Ionin A. A. Kotkov A. K. Kurnosov J. E. McCord A. P. Napartovich L. V. Seleznev N. G. Turkin 《Optics Communications》2000,180(4-6):285-300
Tunable single-line first-overtone (FO) CO lasing on wavelengths from 2.7 up to 4.2 μm corresponding to overtone vibrational transitions from 13→11 up to 38→36 on 413 ro-vibrational lines was experimentally obtained. A parametric study of energetic and spectral characteristics of the single-line FO CO laser was carried out. Energy distribution over ro-vibrational lines was measured. The maximum specific output energy (SOE) came up to 3 J/l Amagat, with single-line output efficiency being up to 0.6%. For the first time, a multi-quantum theoretical model was used to describe the tunable single-line FO CO laser. This multi-quantum approach demonstrated better agreement between theoretical calculations and observed experimental data for laser output as a function of vibrational quantum numbers. 相似文献
996.
用Bohr-Mottelson的两参数、三参数和四参数公式对A~190区61条超形变带进行了系统分析. 结果显示:3个公式都能较好地拟合190区超形变带的E2跃迁谱,而且带首自旋的确定基本一致. 大部分带Bohr-Mottelson的三参数数值关系符合ab公式的理论预期值,小部分带的三参数数值关系符合Harris公式的理论预期值. 一半以上带的四参数数值关系与ab公式的预期值接近,而与Harris公式的预期值偏离较大. 表明两参数ab公式比Harris公式具有更广泛的实用性. 相似文献
997.
利用透射系数研究周期势的能带结构 总被引:4,自引:2,他引:2
利用一维方位势透射系数的递推公式研究了周期势的能带结构,文中考察了能 结构与垒宽、阱宽及位势个数的关系。 相似文献
998.
999.
分析了脱耦合项对于原子核转动惯量的重要影响.总结了奇质量核K=1/2带转动惯量变化规律的新特点.在此基础上讨论了193T1中3条新的超形变带的内部结构.目前尚无足够证据能够确认它们都是K=1/2带. 相似文献
1000.
The size-dependent band structure of an Si phononic crystal(PnC) slab with an air hole is studied by utilizing the non-classic wave equations of the nonlocal strain gradient theory(NSGT). The three-dimensional(3D) non-classic wave equations for the anisotropic material are derived according to the differential form of the NSGT. Based on the the general form of partial differential equation modules in COMSOL, a method is proposed to solve the non-classic wave equations. The bands of the in-plane ... 相似文献