Non-Markovian effects in waveguide-mediated entanglement

We study the generation and evolution of entanglement between two qubits coupled through one-dimensional waveguide modes. By using a complete quantum electrodynamical formalism we go beyond the Markovian approximation. The diagonalization of the Hamiltonian is carried out, and a set of quasi-localized eigenstates is found. We show that when the qubit-waveguide coupling is increased, the Markov approximation is no longer valid, and the generation of entanglement is worsenedThis work was funded by the European Research Council (ERC-2011-AdG Proposal no. 290981) and by the Spanish MINECO under contract MAT2011-28581-C02-0