Entanglement between static and flying qubits in an Aharonov-Bohm double electrometer

TL;DR

This paper explores how electron transport through an Aharonov-Bohm ring interacting with a double quantum dot can generate entanglement between static and flying qubits, revealing conditions for entanglement via phase-coherent transport.

Contribution

It demonstrates a mechanism for entangling a charge qubit with passing electrons using phase-coherent transport in an Aharonov-Bohm ring with symmetric coupling.

Findings

Electrons transmit only when flipping the qubit’s pseudospin parity an odd number of times.

Perfect correlations enable entanglement between the charge qubit and passing electrons.

Entanglement is achieved at specific Aharonov-Bohm flux conditions.

Abstract

We consider the phase-coherent transport of electrons passing through an Aharonov-Bohm ring while interacting with a tunnel charge in a double quantum dot (representing a charge qubit) which couples symmetrically to both arms of the ring. For Aharonov-Bohm flux Phi_AB=h/2e we find that electrons can only be transmitted when they flip the charge qubit's pseudospin parity an odd number of times. The perfect correlations of the dynamics of the pseudospin and individual electronic transmission and reflection events can be used to entangle the charge qubit with an individual passing electron.