We investigate electronic properties of a hierarchical multilayer structure consisting of stacking of barriers and wells. The structure is formed in a sequence of generations, each of which is constructed with the sam...We investigate electronic properties of a hierarchical multilayer structure consisting of stacking of barriers and wells. The structure is formed in a sequence of generations, each of which is constructed with the same pattern but with the previous generation as the basic building blocks. We calculate the transmission spectrum which shows the multifractal behavior for systems with large generation index. From the analysis of the average resistivity and the multifractal structure of the wavefunctions, we show that there exist different types of states exhibiting extended, localized and intermediate characteristics. The degree of localization is sensitive to the variation of the structural parameters.Suggestion of the possible experimental realization is discussed.展开更多
We investigate the phase coherent transport in a single channel system. The theory that the transmission zeros lead to abrupt phase change and in-phase resonances is confirmed numerically in two tight-binding models. ...We investigate the phase coherent transport in a single channel system. The theory that the transmission zeros lead to abrupt phase change and in-phase resonances is confirmed numerically in two tight-binding models. After calculating the eigenvalues and eigenvectors of the Hamiltonians we also confirmed that the same symmetry of the eigenvectors also leads to the abrupt phase change and in-phase resonances that equal the transmission zero.展开更多
文摘We investigate electronic properties of a hierarchical multilayer structure consisting of stacking of barriers and wells. The structure is formed in a sequence of generations, each of which is constructed with the same pattern but with the previous generation as the basic building blocks. We calculate the transmission spectrum which shows the multifractal behavior for systems with large generation index. From the analysis of the average resistivity and the multifractal structure of the wavefunctions, we show that there exist different types of states exhibiting extended, localized and intermediate characteristics. The degree of localization is sensitive to the variation of the structural parameters.Suggestion of the possible experimental realization is discussed.
文摘We investigate the phase coherent transport in a single channel system. The theory that the transmission zeros lead to abrupt phase change and in-phase resonances is confirmed numerically in two tight-binding models. After calculating the eigenvalues and eigenvectors of the Hamiltonians we also confirmed that the same symmetry of the eigenvectors also leads to the abrupt phase change and in-phase resonances that equal the transmission zero.