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991.
Go Yamashita 《Comptes Rendus Mathematique》2011,349(21-22):1127-1130
992.
Osamu Yamashita 《Optics Communications》2011,284(19):4248-4253
A circularly polarized plane wave of infinite transverse extent (δ = ∞) has no spin angular momentum, while a realistic light does carry it. This paradox originates from the presence (δ = ∞) and absence (δ ≈ 0) of the surface integral in the total angular momentum J. The same holds for the torque equation of dJ/dt, so that δ is also connected with the relative Faraday rotation angle ΘF/θF when a radius (a) of a cylindrical medium with optical activity is only a little larger than that (b) of light beam, where ΘF is the Faraday rotation angle and θF is the intrinsic Faraday rotation angle of a medium. It is shown here that it is possible to estimate δ for a realistic light from the drastic variation in ΘF/θF near b/a = 1. 相似文献
993.
Fujii J Sperl M Ueda S Kobayashi K Yamashita Y Kobata M Torelli P Borgatti F Utz M Fadley CS Gray AX Monaco G Back CH van der Laan G Panaccione G 《Physical review letters》2011,107(18):187203
We report x-ray photoemission spectroscopy results on (Ga,Mn)As films as a function of both temperature and Mn doping. Analysis of Mn 2p core level spectra reveals the presence of a distinct electronic screening channel in the bulk, hitherto undetected in more surface sensitive analysis. Comparison with model calculations identifies the character of the Mn 3d electronic states and clarifies the role, and the difference between surface and bulk, of hybridization in mediating the ferromagnetic coupling in (Ga,Mn)As. 相似文献
994.
This Letter reports a convenient method of fabricating a polymer-based microlaser array. Laterally aligned plastic micropillars equipped with an optical resonator were fabricated by using a lithographic technique with an organic-dye-doped photopolymer, which operated as a laser element with a vertical cavity. Under optical pumping, very fine emission spectra showing a Fabry-Perot-type lasing oscillation were observed. Using this technique, integrated laser cavities with desired operation wavebands can be produced easily. 相似文献
995.
996.
997.
This paper is concerned with a class of ellipsoidal sets (ellipsoids and elliptic cylinders) in ${\mathbb{R}^m}$ which are determined by a freely chosen m × m positive semidefinite matrix. All ellipsoidal sets in this class are similar to each other through a parallel transformation and a scaling around their centers by a constant factor. Based on the basic idea of lifting, we first present a conceptual min-max problem to determine an ellipsoidal set with the smallest size in this class which encloses a given subset of ${\mathbb{R}^m}$ . Then we derive a numerically tractable enclosing ellipsoidal set of a given semialgebraic subset of ${\mathbb{R}^m}$ as a convex relaxation of the min-max problem in the lifting space. A main feature of the proposed method is that it is designed to incorporate into existing SDP relaxations with exploiting sparsity for various optimization problems to compute error bounds of their optimal solutions. We discuss how we adapt the method to a standard SDP relaxation for quadratic optimization problems and a sparse variant of Lasserre’s hierarchy SDP relaxation for polynomial optimization problems. Some numerical results on the sensor network localization problem and polynomial optimization problems are also presented. 相似文献
998.
Abstract The time delayed double excitation spectroscopy has been utilized to determine the conversion ratio to F-H center pairs from self-trapped excitons(STEL) at the lowest state (1s[sgrave]g;a1g). The final conversion ratios, ηF/(ηF+ηX), were 0.86, 0.49 and 0.20 for NaCl, KCl and RbCl at 14K, respectively. The conversion efficiency (η =ηF+ηX) from STEL to F-H center pairs(ηF) and to unknown states(ηX) were 0.25, 0.90 and 0.76 for the hole excitation to πg, while 0.03, 0.01 and 0.01 for the electron excitation to b1u, b2u or b3u, in NaCl, KCl and RbCl, respectively. 相似文献
999.
Lauro Tomio A. Delfino T. Frederico M. R. Hadizadeh M. T. Yamashita 《Few-Body Systems》2013,54(1-4):213-216
The fixed-slope correlation between tetramer and trimer binding energies, observed by Tjon in the context of nuclear physics, is mainly a manifestation of the dominance of the two-nucleon force in the nuclear potential, which makes the four-body scale on the order of the three-body one. In a more general four-boson case, the correlation between tetramer and trimer binding energies has a non-fixed slope, which expresses the dependence on the new scale. The associated scaling function generates a family of Tjon lines. This conclusion relies on a recent study with weakly-bound four identical bosons, within a renormalized zero-range Faddeev-Yakubovsky formalism. 相似文献
1000.
M. Hidaka A. Noda Z. Y. Zhou S. Yamashita H. Fujii B. M. Wanklyn 《Phase Transitions》2013,86(4):199-218
Successive structural transitions of RbVF4 have been studied with extended X-ray absorption fine structure (EXAFS) of Rb ions. It is found that there are some modulations in the pre-edge and post-edge regions of the X-ray absorption spectrum in the vicinity of the structural phase transitions above room temperature. By analyzing the EXAFS, it is also found that local spatial distortions around the Rb ions are induced at the structural transitions. 相似文献