1999/01/18 by Gi-Yeong Oh · 1 citation
Physics and Astronomy · #Quantum and electron transport phenomena #Semiconductor Quantum Structures and Devices #Topological Materials and Phenomena #cond-mat.dis-nn #cond-mat.mes-hall
paper · pdf · doi:10.1103/physrevb.60.1939
published as Phys. Rev. B 60, 1939 (1999) · 7 pages (in two-column), 10 figures (including 2 tables)
arxiv created 1999/01/18 · openalex publication_date 1999/07/15 · arxiv updated 2009/11/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We study the effect of spatially modulated magnetic fields on the energy spectrum of a two-dimensional Bloch electron. By taking into account four kinds of modulated fields and using the method of direct diagonalization of the Hamiltonian matrix, we calculate energy spectra with varying system parameters (i.e., the kind of the modulation, the relative strength of the modulated field to the uniform background field, and the period of the modulation) to elucidate that the energy band structure sensitively depends on such parameters: Inclusion of spatially modulated fields into a uniform field leads to the occurrence of gap opening, gap closing, band crossing, and band broadening, resulting in an energy band structure that is distinct from the Hofstadter's spectrum. We also discuss in detail the effect of the field modulation on the symmetries appearing in the Hofstadter's spectrum.