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arXiv · 1503.00776

Majorana zero modes choose Euler numbers - revealed by full counting statistics

Dong E. Liu·Alex Levchenko·Roman M. Lutchyn
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Abstract

We study transport properties of a quantum dot coupled to a Majorana zero mode and two normal leads. We investigate the full counting statistics of charge tunneling events which allows one to extract complete information about current fluctuations. Using a Keldysh path-integral approach, we compute the cumulant generating function. We first consider a noninteracting spinless regime, and find that for the symmetric dot-lead couplings, the zero-frequency cumulants exhibit a universal pattern of Euler numbers, independent of the microscopic parameters. For a spinful case, the Coulomb interaction effects are discussed for both strong interaction (single-electron occupancy regime) and weak interactions (perturbative regime). Compared to the case without Majorana coupling, we show that, while the tunneling conductance might exhibit zero-bias anomaly, the full counting statistics is qualitatively different in the presence of the Majorana coupling.

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Dong E. Liu, Alex Levchenko, Roman M. Lutchyn. 2015-03-02. Majorana zero modes choose Euler numbers - revealed by full counting statistics. https://doi.org/10.1103/physrevb.92.205422

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