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تسجيل مستخدم جديدSystematic construction of topological flat-band models by molecular-orbital representation
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On the basis of the molecular-orbital representation which describes generic flat-band models, we propose a systematic way to construct a class of flat-band models with finite-range hoppings that have topological natures. In these models, the topological natures are encoded not into the flat band itself but into the dispersive bands touching the flat band. Such a band structure may become a source of exotic phenomena arising from the combination of flat bands, topology and correlations.
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We calculate correlation functions of exactly-solvable one-dimensional flat-band models by utilizing the molecular-orbital representation. The models considered in this paper have a gapped ground state with flat-band being fully occupied, even in the
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