ar X iv : c on d - m at / 9 60 72 23 v 1 3 1 Ju l 1 99 6 Hofstadter butterflies for flat bands
نویسنده
چکیده
Hofstadter’s diagram, or the energy spectrum against the magnetic field in tight-binding systems, is obtained for the models having flat (dispersionless) one-electron band(s) that have originally been proposed for itinerant spin ferromagnetism. Magnetic fields preserve those flat bands that arise from a topological reason, while dispersions emerge in a singular manner for the flat bands arising from interference, implying an anomalous orbital magnetism. PACS numbers: 72.15.Gd, 71.70.Di Typeset using REVTEX
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تاریخ انتشار 1996