Detecting Majorana fermions by nonlocal entanglement between quantum dots

TL;DR

This paper proposes a method to detect Majorana fermions by observing nonlocal entanglement between two quantum dots, which is a signature of the nonlocal fermion level formed by Majorana modes in a topological superconductor.

Contribution

It introduces a scheme to identify Majorana fermions through nonlocal entanglement measurements between quantum dots coupled to a topological superconductor.

Findings

Nonlocal entanglement can be generated via Majorana fermions.

Measurement of one quantum dot influences the other, indicating nonlocality.

Charging energy enhances the entanglement signature.

Abstract

Nonlocal entanglement between two quantum dots can be generated through Majorana fermions. The two Majorana fermions at the ends of an one-dimensional topological superconductor form a nonlocal fermion level, coupling to the occupation states of two quantum dots put close to the two ends, and the entire system will come into an entangled state. After introducing a charging energy by a capacitor, entanglement of the entire system can manifest itself through the nonlocal entanglement between the two quantum dots. That is, when measuring the electron occupations of the quantum dots, the measurement result of one quantum dot will influence the measurement result of the other quantum dot. This nonlocal entanglement between the two quantum dots is a strong evidence of the nonlocal nature of the fermion level constructed by two Majorana fermions.