Eur. Phys. J. D 58, 397-401 (2010)
https://doi.org/10.1140/epjd/e2010-00087-6

Entanglement sudden death in band gaps

¹ Shandong Provincial Key Laboratory of Laser Polarization and Information Technology, Department of Physics, Qufu Normal University, Qufu, 273165, PR China
² Key Laboratory of Quantum Information, Department of Physics, University of Science and technology of China, Hefei, 230026, PR China

Corresponding author: ^a yjxia@mail.qfnu.edu.cn

Received: 19 January 2010
Published online: 6 April 2010

Abstract

Using the pseudomode method, we evaluate exactly time-dependent entanglement for two independent qubits, each coupled to a non-Markovian structured environment. Our results suggest a possible way to retard entanglement sudden death by modifying the qubit-pseudomode detuning and the spectrum of the reservoirs. Particularly, in environments structured by a model of a density-of-states gap which has two poles, entanglement trapping and prevention of entanglement sudden death occur in the weak-coupling regime.