Dynamics of Entanglement between a Quantum Dot Spin Qubit and a Photon Qubit inside a Semiconductor High-Q Nanocavity

Abstract EN

We investigate in this paper the dynamics of entanglement between a QD spin qubit and a single photon qubit inside a quantum network node, as well as its robustness against various decoherence processes.

First, the entanglement dynamics is considered without decoherence.

In the small detuning regime (Δ=78 μeV), there are three different conditions for maximum entanglement, which occur after 71, 93, and 116 picoseconds of interaction time.

In the large detuning regime (Δ=1.5 meV), there is only one peak for maximum entanglement occurring at 625 picoseconds.

Second, the entanglement dynamics is considered with decoherence by including the effects of spin-nucleus and hole-nucleus hyperfine interactions.

In the small detuning regime, a decent amount of entanglement (35% entanglement) can only be obtained within 200 picoseconds of interaction.

Afterward, all entanglement is lost.

In the large detuning regime, a smaller amount of entanglement is realized, namely, 25%.

And, it lasts only within the first 300 picoseconds.