Abstract

We study the quantum entanglement of a two-qubit system interacting with single-frequency plasmonic excitations. Under the exact resonance condition and in the presence of both the Stark shift and phase shift, an exact solution of the time evolution of the unitary operator is obtained. Employing this solution an analytical expression for time evolution of the negative eigenvalues for the partial transposition of the density operator is obtained. Numerical investigations are carried out for the entanglement with different values of Stark shift and plasmonic excitations. It is shown that, the entanglement is affected by the plasmonic excitation and the Stark shift.

© 2008 Optical Society of America