Entanglement of Two, Three, and Four Quantum Dots in Hybrid Quantum Dot/Plasmonic Systems

We use cavity quantum electrodynamics to study systems composed of two, three, and four two-state quantum dots in proximity to a plasmonic system such as a metal nanoparticle or an array of metal nanoparticles. We find that significant essential (all dot) entanglement, as measured by concurrence, in the two and four quantum dot cases is possible. At present the three quantum dot case lacks an easily applied measure of entanglement, but multiple bipartite entanglements are demonstrated. Moreover, we show that one can induce entanglement in two and three quantum dot systems starting from the ground state by use of pulsed excitations. These results represent a promising advance for the eventual use of quantum dots, coupled to one another through a dissipative structure such as a plasmonic system, in quantum computation.