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Detecting Majorana fermions by use of superconductor-quantum Hall liquid junctions

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 نشر من قبل Zheng-Wei Zuo
 تاريخ النشر 2016
  مجال البحث فيزياء
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The point contact tunnel junctions between a one-dimensional topological superconductor and single-channel quantum Hall (QH) liquids are investigated theoretically with bosonization technology and renormalization group methods. For the $ u=1$ integer QH liquid, the universal low-energy tunneling transport is governed by the perfect Andreev reflection fixed point with quantized zero-bias conductance $G(0)=2e^{2}/h$, which can serve as a definitive fingerprint of the existence of a Majorana fermion. For the $ u =1/m$ Laughlin fractional QH liquids, its transport is governed by the perfect normal reflection fixed point with vanishing zero-bias conductance and bias-dependent conductance $G(V) sim V^{m-2}$. Our setup is within reach of present experimental techniques.



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