Europhys. Lett.
Volume 76, Number 5, December 2006
Page(s) 905 - 911
Section Condensed matter: electronic structure, electrical, magnetic, and optical properties
Published online 01 November 2006
Europhys. Lett., 76 (5), pp. 905-911 (2006)
DOI: 10.1209/epl/i2006-10342-y

Charge qubit entanglement in double quantum dots

S. Weiss, M. Thorwart and R. Egger

Institut für Theoretische Physik, Heinrich-Heine-Universität D-40225 Düsseldorf, Germany

received 21 July 2006; accepted in final form 4 October 2006
published online 1 November 2006

We study entanglement of charge qubits in a vertical tunnel-coupled double quantum dot containing two interacting electrons. Exact diagonalization is used to compute the negativity characterizing entanglement. We find that entanglement can be efficiently generated and controlled by sidegate voltages, and describe how it can be detected. For large enough tunnel coupling, the negativity shows a pronounced maximum at an intermediate interaction strength within the Wigner molecule regime.

73.21.La - Quantum dots.
03.65.Ud - Entanglement and quantum nonlocality (e.g. EPR paradox, Bell's inequalities, GHZ states, etc.).
73.23.-b - Electronic transport in mesoscopic systems.

© EDP Sciences 2006