Extended electron states and magnetotransport in a 3-simplex fractal

Article

关键词: SIERPINSKI GASKET;    MAGNETIC-FIELD;    HIERARCHICAL LATTICES;    SCHRODINGER-EQUATION;    GREEN-FUNCTIONS;    SPECTRUM;    LOCALIZATION;    SUPERLOCALIZATION;    TRANSPORT;    DISORDER;   

DOI  :  10.1103/PhysRevB.72.134207

来源: SCIE

【 摘 要 】

We perform a real space renormalization group analysis to study the one electron eigenstates and the transmission coefficient across a 3-simplex fractal lattice of arbitrary size, in the presence of a magnetic field. In particular, we discuss the existence of extended electronic states and the influence of the magnetic field on the spectrum of the system. A general formulation is presented which enables us to deal with both the isotropic and the anisotropic cases. It is found that, in general, the transmission across an anisotropic fractal is larger than its isotropic counterpart. Additionally, we point out an interesting correlation between a subset of values of the external field, and the multiple fixed point cycles of the Hamiltonian corresponding to the extended eigenstates. A prescription for observing such a correlation is proposed. This aspect may be important in the classification of the extended states in such deterministic structures.

【 授权许可】

Free