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arXiv · 1503.06801

Conductance spectroscopy of topological superconductor wire junctions

F. Setiawan·P. M. R. Brydon·Jay D. Sau·S. Das Sarma
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Abstract

We study the zero-temperature transport properties of one-dimensional normal-superconductor (NS) junctions with topological superconductors across their topological transitions. Working within the Blonder-Tinkham-Klapwijk (BTK) formalism generalized for topological NS junctions, we analytically calculate the differential conductance for tunneling into two models of a topological superconductor: a spinless intrinsic $p$-wave superconductor and a spin-orbit-coupled $s$-wave superconductor in a Zeeman field. In both cases we verify that the zero-bias conductance is robustly quantized at $2e^2/h$ in the topological regime, while it takes nonuniversal values in the non-topological phase. The conductance spectra in the topological state develops a peak at zero bias for certain parameter regimes, with the peak width controlled by the strength of spin-orbit coupling and barrier transparency.

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F. Setiawan, P. M. R. Brydon, Jay D. Sau, S. Das Sarma. 2015-11-05. Conductance spectroscopy of topological superconductor wire junctions. https://doi.org/10.1103/physrevb.91.214513

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