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arXiv · 1509.00463

Current Correlations in a Majorana Beam Splitter

Arbel Haim·Erez Berg·Felix von Oppen·Yuval Oreg
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Abstract

We study current correlations in a $T$-junction composed of a grounded topological superconductor and of two normal-metal leads which are biased at a voltage $V$. We show that the existence of an isolated Majorana zero mode in the junction dictates a universal behavior for the cross correlation of the currents through the two normal-metal leads of the junction. The cross correlation is negative and approaches zero at high bias voltages as -1/$V$. This behavior is robust in the presence of disorder and multiple transverse channels, and persists at finite temperatures. In contrast, an accidental low-energy Andreev bound state gives rise to nonuniversal behavior of the cross correlation. We employ numerical transport simulations to corroborate our conclusions.

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Arbel Haim, Erez Berg, Felix von Oppen, Yuval Oreg. 2015-12-15. Current Correlations in a Majorana Beam Splitter. https://doi.org/10.1103/physrevb.92.245112

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