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941.
942.
Ota T Rontani M Tarucha S Nakata Y Song HZ Miyazawa T Usuki T Takatsu M Yokoyama N 《Physical review letters》2005,95(23):236801
We study electronic configurations in a single pair of vertically coupled self-assembled InAs quantum dots, holding just a few electrons. By comparing the experimental data of nonlinear single-electron transport spectra in a magnetic field with many-body calculations, we identify the spin and orbital configurations to confirm the formation of molecular states by filling both the quantum mechanically coupled symmetric and antisymmetric states. Filling of the antisymmetric states is less favored with increasing magnetic field, and this leads to various magnetic field induced transitions in the molecular states. 相似文献
943.
We investigate numerically with the aid of the Landau-de Gennes continuum theory the interaction between two spherical particles carrying the same topological charges +1 mediated by the elastic distortion of a nematic liquid crystal. We consider the case where an escaped nontopological ring disclination is situated between the particles; the director is continuous everywhere and no counterdefects are present. We find that the interaction is attractive and its potential energy depends linearly on the interparticle distance D. This behavior yields the D-independent interaction force, which was observed experimentally by Poulin, Cabuil, and Weitz [Phys. Rev. Lett. 79, 4862 (1997)] in the presence of narrow strings of birefringent regions ("bubble-gum" configuration) between the particles. 相似文献
944.
We report on the demonstration of surface-emitted terahertz- (THz-) wave difference-frequency generation from two-dimensional (2D) periodically poled lithium niobate (PPLN). The two orthogonal periodic structures individually compensate for both the phase mismatch of the launched lasers and the generated THz wave. Tunable 1.5-1.8 THz wave generation with a bandwidth of 10-GHz was obtained by use of two 2D PPLN crystals. We also confirmed that THz waves were simultaneously generated into two opposite directions, which suggests the possibility of higher THz-wave output power. 相似文献
945.
We have studied the explicit relation between the gauge-invariant path-ordered operator (POO) and a string field in two dimensions. For this purpose, we use the hamiltonian of two-dimensional quantum chromodynamics reformulated in terms of POO. POO is expanded in a power series of a non-local bosonic operator. We show that such a bosonic operator describes Bars and Hanson's free string field in the second quantization. Interactions among bosonic operators are treated in perturbation theory. The coupling constant is proportional to 1/√Nc. 相似文献
946.
Transient spectroscopic techniques have been used to discriminate between various processes forming excited Cu II levels in a Ne-Cu discharge. Ratio of the cross sections for Ne+-Cu charge transfer reaction into individual Cu II 5s levels has been determined. The Cu II 4p levels were found to be excited through some unidentified process as well as Ne(metastable) -Cu Penning reaction, and the former was more effective. 相似文献
947.
948.
Kenji Yokoyama 《Chemical physics letters》1982,89(1):93-96
Time-resolved resonance Raman spectra of the lowest state of N,N,N′,N′-tetramethyl-p-phenylenediamine (3TMPD) were observed in solution at room temperature. A new Raman band observed at 1530 cm?1 was assigned to 3TMPD. 相似文献
949.
M Iwai I Kohda C Fukaya Y Naito K Yokoyama H Nakajima K Tsujikawa M Okabe T Mimura 《Chemical & pharmaceutical bulletin》1987,35(11):4616-4625
950.