Generation of Spin Entanglement in Nonequilibrium Quantum Dots

TL;DR

This paper proposes methods to generate and enhance spin entanglement between two quantum dots in nonequilibrium conditions, producing Werner states with fidelity above 1/2, indicating entanglement.

Contribution

It introduces schemes for creating spatially-separated spin entanglement in quantum dots under nonequilibrium conditions, highlighting increased entanglement probability.

Findings

Enhanced spin entanglement probability in nonequilibrium states

Generation of Werner states with spin singlet fidelity > 1/2

Entanglement achieved in both transient and steady states

Abstract

We propose schemes for generating spatially-separated spin entanglement in systems of two quantum dots with onsite Coulomb repulsion weakly coupled to a joint electron reservoir. An enhanced probability for the formation of spin entanglement is found in nonequilibrium situations with one extra electron on each dot, either in the transient state after rapid changes of the gate voltage, or in the steady state with applied bias voltage. In both cases so-called Werner states with spin singlet fidelity exceeding 1/2 are generated, which indicates entanglement.