Entanglement trapping in structured environments

We highlight the direct link between the time-dependent entanglement and single-qubit excited-state population for two independent qubits, each coupled to a zero-temperature bosonic environment. We show that, in environments structured so as to inhibit spontaneous emission, entanglement trapping and thus prevention of entanglement sudden death occur. We explicitly show that, for photonic band-gap materials as environment, high values of entanglement trapping can be achieved. We finally discuss how, under these conditions, coherent quantum operations can be implemented.