Electron Raman scattering （ERS） is investigated in a spherical HgS/CdS quantum dot quantum well （QDQW）. The differential cross section （DCS） is calculated as a function of the scattering frequency and the sizes ...Electron Raman scattering （ERS） is investigated in a spherical HgS/CdS quantum dot quantum well （QDQW）. The differential cross section （DCS） is calculated as a function of the scattering frequency and the sizes of QDQW. Single parabolic conduction and valence bands are assumed. The selection rules for the processes are studied. Singularities in the spectra are found and interpreted. The ERS studied here can be used to provide direct information about the electron band structure of these systems.展开更多
Electron Raman scattering（ERS） is investigated in a CdS cylindrical quantum dot（QD）.The differential cross section is calculated as a function of the scattering frequency and the size of the QD.Single parabolic co...Electron Raman scattering（ERS） is investigated in a CdS cylindrical quantum dot（QD）.The differential cross section is calculated as a function of the scattering frequency and the size of the QD.Single parabolic conduction and valence bands are assumed,and singularities in the spectrum are found and interpreted.The selection rules for the processes are also studied.The ERS studied here can be used to provide direct information about the electron band structure of these systems.展开更多
The differential cross-section for electronic Raman scattering in double semi-parabolic quantum wells of typical GaAs/AlxGa1-xAs is investigated numerically with the effective-mass approximation. The dependence of the...The differential cross-section for electronic Raman scattering in double semi-parabolic quantum wells of typical GaAs/AlxGa1-xAs is investigated numerically with the effective-mass approximation. The dependence of the differential cross-section on structural parameters such as the barrier width and the well widths is studied. Our results indicate that the electronic Raman scattering is affected by the geometrical size and can be negligible in the symmetric double-well case.展开更多
This paper employs micro-Raman technique for detailed analysis of the defects （both inside and outside） in bulk 4H-SiC. The main peaks of the first-order Raman spectrum obtained in the centre of defect agree well wi...This paper employs micro-Raman technique for detailed analysis of the defects （both inside and outside） in bulk 4H-SiC. The main peaks of the first-order Raman spectrum obtained in the centre of defect agree well with those of perfect bulk 4H-SiC, which indicate that there is no parasitic polytype in the round pit and the hexagonal defect. Four electronic Raman scattering peaks from nitrogen defect levels are observed in the round pit （395 cm^-1, 526 cm^-1, 572cm^-1, and 635cm^-1）, but cannot be found in the spectra of hexagonal defect. The theoretical analysis of the longitudinal optical plasmon-phonon coupled mode line shape indicates the nonuniformity of nitrogen distribution between the hexagonal defect and the outer area in 4H-SiC. The second-order Raman features of the defects in bulk 4H-SiC are well-defined using the selection rules for second-order scattering in wurtzite structure and compared with that in the free defect zone.展开更多
基金Project supported by the Guangdong Provincial Natural Science Foundation(No.S2012010010976)
文摘Electron Raman scattering （ERS） is investigated in a spherical HgS/CdS quantum dot quantum well （QDQW）. The differential cross section （DCS） is calculated as a function of the scattering frequency and the sizes of QDQW. Single parabolic conduction and valence bands are assumed. The selection rules for the processes are studied. Singularities in the spectra are found and interpreted. The ERS studied here can be used to provide direct information about the electron band structure of these systems.
文摘Electron Raman scattering（ERS） is investigated in a CdS cylindrical quantum dot（QD）.The differential cross section is calculated as a function of the scattering frequency and the size of the QD.Single parabolic conduction and valence bands are assumed,and singularities in the spectrum are found and interpreted.The selection rules for the processes are also studied.The ERS studied here can be used to provide direct information about the electron band structure of these systems.
基金Project supported by the Shiraz University of Technology, Iran
文摘The differential cross-section for electronic Raman scattering in double semi-parabolic quantum wells of typical GaAs/AlxGa1-xAs is investigated numerically with the effective-mass approximation. The dependence of the differential cross-section on structural parameters such as the barrier width and the well widths is studied. Our results indicate that the electronic Raman scattering is affected by the geometrical size and can be negligible in the symmetric double-well case.
基金supported by the National Defense Pre-Research Foundation of China (Grant Nos 51308030201 and 51323040118)
文摘This paper employs micro-Raman technique for detailed analysis of the defects （both inside and outside） in bulk 4H-SiC. The main peaks of the first-order Raman spectrum obtained in the centre of defect agree well with those of perfect bulk 4H-SiC, which indicate that there is no parasitic polytype in the round pit and the hexagonal defect. Four electronic Raman scattering peaks from nitrogen defect levels are observed in the round pit （395 cm^-1, 526 cm^-1, 572cm^-1, and 635cm^-1）, but cannot be found in the spectra of hexagonal defect. The theoretical analysis of the longitudinal optical plasmon-phonon coupled mode line shape indicates the nonuniformity of nitrogen distribution between the hexagonal defect and the outer area in 4H-SiC. The second-order Raman features of the defects in bulk 4H-SiC are well-defined using the selection rules for second-order scattering in wurtzite structure and compared with that in the free defect zone.
