Landau levels in quasicrystals

Article

关键词: MAGNETIC-FIELD;    WAVE-FUNCTIONS;    ELECTRONS;    SYSTEMS;    APPROXIMANTS;    TILINGS;    LATTICE;   

DOI  :  10.1103/PhysRevB.98.165427

来源: SCIE

【 摘 要 】

Two-dimensional tight-binding models for quasicrystals made of plaquettes with commensurate areas are considered. Their energy spectrum is computed as a function of an applied perpendicular magnetic field. Landau levels are found to emerge near band edges in the zero-field limit. Their existence is related to an effective zero-field dispersion relation valid in the continuum limit. For quasicrystals studied here, an underlying periodic crystal exists and provides a natural interpretation to this dispersion relation. In addition to the slope (effective mass) of Landau levels, we also study their width as a function of the magnetic flux and identify two fundamental broadening mechanisms: (i) tunneling between closed cyclotron orbits and (ii) individual energy displacement of states within a Landau level. Interestingly, the typical broadening of the Landau levels is found to behave algebraically with the magnetic field with a nonuniversal exponent.

【 授权许可】

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