Shot noise in a toroidal carbon nanotube coupled with Majorana fermion states

• The toroidal carbon nanotube interferometer coupled with Majorana fermions is considered.
• The terminal current and shot noise have been investigated through equation of motion method.
• The Andreev and cross-Andreev reflections contribute to the current and shot noise.
• The enhancement of shot noise is generated by the application of Majorana fermions.
• The periodic oscillations versus Aharonov–Bohm flux exhibit the controlling of Majorana fermions.

The shot noise of a toroidal carbon nanotube (TCN) interferometer coupled with Majorana fermions is deduced from evaluating the current correlation. Many novel channels are opened for electrons to transport, and the energy gap of the semiconducting TCN becomes narrower. The Majorana fermions cause additional current correlations among the normal tunneling currents and Andreev reflection currents, and hence the shot noise and Fano factor are enhanced. The conductance, current, and shot noise are modified by Majorana fermions to exhibit different oscillation and resonance structures. The detailed behaviors of these quantities are quite different from the metal and semiconducting TCNs.