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S. Tomita M. Kato K. Maki 《Physica C: Superconductivity and its Applications》2009,469(15-20):1074-1076
For analyzing the checker-board like modulation of the local density of states (LDOS) around a vortex observed in the slightly overdoped Bi2Sr2CaCu2Ox, we examined the effect of pseudogap state of high-Tc superconductors to the LDOS around the vortex. We first derived the Bogoliubov-de Gennes equation for d-wave superconductivity (d-SC) in the presence of d-spin density wave (d-SDW). Using the Fourier–Bessel expansion, we solved this equation for a single vortex state, numerically. We found that the peak of the bound states around E = 0 becomes small and modulation of the LDOS is observed for larger d-SDW order parameter. 相似文献
105.
The memory effect upon glassification is studied in the glass-to-rubber transition of vulcanized rubber with the strain as a controlling parameter. A phenomenological model is proposed, taking the history of the temperature and the strain into account, by which the experimental results are interpreted. The data and the model demonstrate that the glassy state memorizes the time course of strain upon glassification, not as a single parameter but as the history itself. The data also show that the effect of irreversible deformation in the glassy state is beyond the scope of the present model. 相似文献
106.
A multiwavelength, multistripe tunable laser array is proposed, and its application to absorption spectroscopy is demonstrated. Laser waveguides doped with Rhodamine 6 G dye were integrated on a plastic chip, and simultaneous output at different wavelengths was obtained by use of a distributed-feedback technique. A very low threshold of 3 muJ was attained, and spectrally narrowed output (<0.1 nm) was obtained. A scheme for digital spectroscopy is also proposed based on this laser array, and absorption spectroscopy of sodium atoms without wavelength scanning is demonstrated by use of a sodium-vapor cell. 相似文献
107.
The effect of inelastic scattering on the electron reflection in multi-quantum barriers (MQBs) has been examined using the damped resonant tunnelling model for the first time. The electron reflectivity in the virtual barrier region for unstrained GalnAs/InP MQB deteriorates below 100% by about 10% for phase relaxation time of 0.22ps. We propose a strain-compensated GalnAs/GalnP MQB which not only has virtual barrier 4 times as high as that of an unstrained MQB, but whose reflectivity deterioration is reduced to less than 5% in comparison with 10% for unstrained MQB for the same phase relaxation time. We have also successfully grown a Ga0.25In0.75As (1.5% compressive) well/Ga0.25In0.75P (1.2% tensile) barrier short-period superlattice with six wells by chemical beam epitaxy, which exhibits the possibility of fabrication of the strain-compensated MQBs. 相似文献
108.
The integral equation for the distribution function of the effective fields in the random Ising model in the finite external field is solved exactly at zero temperature in the one-dimensional case for 1) dilute ferromagnet, 2) dilute antiferromagnet and 3) ±J model. The ground state characteristics of these systems are obtained. In particular the effective fields in the ±J model are shown to have a triangular distribution in the zero external field limit. 相似文献
109.
Let denote the set of all Hadamard matrices of order n. For , define the weight of H to be the number of 1's in H and is denoted by w(H). For a subset , define the maximal weight of Γ as w(Γ) = max{w(H) | H?Γ}. Two Hadamard matrices are equivalent if one of them can be transformed to the other by permutation and negation of rows and columns, and the equivalence class containing H is denoted by [H]. In this paper, we shall derive lower bounds for w([H]), which are best possible for n ? 20. We shall also determine the exact value of . 相似文献
110.
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