Inducing spin-correlations and entanglement in a double quantum dot through non-equilibrium transport

TL;DR

This paper demonstrates how non-equilibrium transport, flux, and current can be used to induce and control spin correlations and entanglement in a double quantum dot system, with results supported by advanced simulations.

Contribution

It introduces a method to engineer entangled states in double quantum dots via current-driven spin correlations, accounting for many-body effects.

Findings

Current can induce spin correlations in initially uncorrelated dots.

Entangled states can be engineered through non-equilibrium transport.

Results explained by Ruderman-Kittel-Kasuya-Yoshida physics.

Abstract

For a double quantum dot system in a parallel geometry, we demonstrate that by combining the effects of a flux and driving an electrical current through the structure, the spin correlations between electrons localized in the dots can be controlled at will. In particular, a current can induce spin correlations even if the spins are uncorrelated in the initial equilibrium state. Therefore, we are able to engineer an entangled state in this double-dot structure. We take many-body correlations fully into account by simulating the real-time dynamics using the time-dependent density matrix renormalization group method. Using a canonical transformation, we provide an intuitive explanation for our results, related to Ruderman-Kittel-Kasuya-Yoshida physics driven by the bias.