Summary: | 碩士 === 淡江大學 === 物理學系碩士班 === 99 === In this thesis ,we perform first-principles calculations to explore the properties strongly bound Frenkel-like excitons. According to the local character ,the wavefunction of Frenkel-like exciton can be represented by the Wannier function in our study. Furthermore ,electronic correlation function and response function can be obtained by solving the Bethe-Salpeter equation with the help of developing two-particle kinetic kernel(T). Our result can be compared with the measurement of inelastic X-ray scattering. Practically ,we focus on the dynamical properties of strongly bound exciton in two-dimensional SiC sheet and BN sheet. Meanwhile ,our results show that exciton could be propagated along the direction perpendicular to the sheet plane by reducing the inter-sheet distance.
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