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arXiv · 1409.3860

Probing Majorana Physics in Quantum Dot Shot Noise Experiments

Dong E. Liu·Meng Cheng·Roman M. Lutchyn
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Abstract

We consider a quantum dot coupled to a topological superconductor and two normal leads and study transport properties of the system. Using Keldysh path-integral approach, we study current fluctuations (shot noise) within the low-energy effective theory. We argue that the combination of the tunneling conductance and the shot noise through a quantum dot allows one to distinguish between the topological (Majorana) and non-topological (e.g., Kondo) origin of the zero-bias conduction peak. Specifically, we show that, while the tunneling conductance might exhibit zero-bias anomaly due to Majorana or Kondo physics, the shot noise is qualitatively different in the presence of Majorana zero modes.

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Dong E. Liu, Meng Cheng, Roman M. Lutchyn. 2015-04-07. Probing Majorana Physics in Quantum Dot Shot Noise Experiments. https://doi.org/10.1103/physrevb.91.081405

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