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Plancks quantum-driven integer quantum Hall effect in chaos

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 نشر من قبل Chushun Tian
 تاريخ النشر 2014
  مجال البحث فيزياء
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The integer quantum Hall effect (IQHE) and chaos are commonly conceived as being unrelated. Contrary to common wisdoms, we find in a canonical chaotic system, the kicked spin-$1/2$ rotor, a Plancks quantum($h_e$)-driven phenomenon bearing a firm analogy to IQHE but of chaos origin. Specifically, the rotors energy growth is unbounded (metallic phase) for a discrete set of critical $h_e$-values, but otherwise bounded (insulating phase). The latter phase is topological in nature and characterized by a quantum number (quantized Hall conductance). The number jumps by unity whenever $h_e$ decreases passing through each critical value. Our findings, within the reach of cold-atom experiments, indicate that rich topological quantum phenomena may emerge from chaos.



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