Isolated flat bands and spin-1 conical bands in two-dimensional lattices
نویسندگان
چکیده
منابع مشابه
Topological flat bands from dipolar spin systems.
We propose and analyze a physical system that naturally admits two-dimensional topological nearly flat bands. Our approach utilizes an array of three-level dipoles (effective S=1 spins) driven by inhomogeneous electromagnetic fields. The dipolar interactions produce arbitrary uniform background gauge fields for an effective collection of conserved hard-core bosons, namely, the dressed spin flip...
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Recently spin-orbit (SO)-coupled superfluids in free space or harmonic traps have been extensively studied, motivated by the recent experimental realization of SO coupling for Bose-Einstein condensates (BEC). However, the rich physics of SO-coupled BEC in optical lattices has been largely unexplored. In this paper, we show that in a suitable parameter region the lowest Bloch state forms an isol...
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ژورنال
عنوان ژورنال: Physical Review B
سال: 2010
ISSN: 1098-0121,1550-235X
DOI: 10.1103/physrevb.82.075104