High-concurrence steady-state entanglement of two hole spins in a quantum dot molecular

TL;DR

This paper proposes a novel optical pumping method to generate and stabilize high-concurrence steady-state entanglement of two hole spins in a quantum dot molecule, resilient to environmental effects and achievable at low temperatures.

Contribution

It introduces a new scheme using spontaneous emission for entanglement stabilization without state initialization, considering phonon and tunneling effects.

Findings

Concurrence over 0.95 at 1 K temperature.

High-rate stabilization of entanglement via optical pumping.

Generation of two-qubit singlet state without initial state preparation.

Abstract

Entanglement, a non-trivial phenomena manifested in composite quantum system, can be served as a new type of physical resource in the emerging technology of quantum information and quantum computation. However, a quantum entanglement is fragile to the environmental-induced decoherence. Here, we present a novel way to prepare a high-concurrence steady-state entanglement of two hole spins in a quantum dot molecular via optical pumping of trion levels. In this scheme, the spontaneous dispassion is used to induce and stabilize the entanglement with rapid rate. It is firstly shown that under certain conditions, two-qubit singlet state can be generated without requiring the state initialization. Then we study the effect of acoustic phonons and electron tunnelings on the scheme, and show that the concurrence of entangled state can be over 0.95 at temperature $T = 1 $K.