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

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.