Finite Time Disentanglement Mediated by Plasmons for Different Waveguide Geometries

Abstract

In this thesis, entanglement dynamics of two distant qubits placed at a height h from plasmonic waveguide are investigated. For this purpose, two waveg uide geometries are considered (i) cylindrical nanowire and (ii) V-shaped channel. To see the evolution of the system, Markovian master equation approach is used and density matrix elements are extracted. Entanglement generation is evaluated for ideal plasmonic waveguide and realistic channel waveguide. The influence of decay rates and coupling parameters on en tanglement dynamics is analyzed. Moreover, entanglement sudden death is examined at specific qubit-qubit separation for different initial states. At later time, entanglement rebirth is observed and dark period is estimated for both geometries. It is noticed that the cylindrical geometry shows lesser dark period as compared to the V-shaped channel and the revival of entanglement is much more significant in perior waveguide geometry as compared to the lateral. Further, super dense coding as an application of quantum entanglement is also examined for certain initial states and it is observed that the optimal time of dense coding capacity is greater for the case of cylindrical geometry as compared to V-shaped channel.