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arXiv · 1009.5542

Quantized conductance at the Majorana phase transition in a disordered superconducting wire

A. R. Akhmerov·J. P. Dahlhaus·F. Hassler·M. Wimmer·C. W. J. Beenakker
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Abstract

Superconducting wires without time-reversal and spin-rotation symmetries can be driven into a topological phase that supports Majorana bound states. Direct detection of these zero-energy states is complicated by the proliferation of low-lying excitations in a disordered multi-mode wire. We show that the phase transition itself is signaled by a quantized thermal conductance and electrical shot noise power, irrespective of the degree of disorder. In a ring geometry, the phase transition is signaled by a period doubling of the magnetoconductance oscillations. These signatures directly follow from the identification of the sign of the determinant of the reflection matrix as a topological quantum number.

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A. R. Akhmerov, J. P. Dahlhaus, F. Hassler, M. Wimmer, C. W. J. Beenakker. 2010-11-30. Quantized conductance at the Majorana phase transition in a disordered superconducting wire. https://doi.org/10.1103/physrevlett.106.057001

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