Modulated Entanglement Evolution Via Correlated Noises

We study entanglement dynamics in the presence of correlated environmental noises. Specifically, we investigate the quantum entanglement dynamics of two spins in the presence of correlated classical white noises, deriving Markov master equation and obtaining explicit solutions for several interesting classes of initial states including Bell states and X form density matrices. We show how entanglement can be enhanced or reduced by the correlation between the two participating noises.Comment: 9 pages, 4 figures. To be published in Quantum Information Processing, special issue on Quantum Decoherence and Entanglemen

Natural dynamics of spin chains

In this thesis, we discuss the natural dynamics of spin chains with regards to their potential role as information carriers in quantum computers and also standalone uses in a quantum computational context. We discuss a range of spin chain devices, expanding existing results on linear chains and simple branched devices to more complex geometries and circular devices. Over the course of this work, we analyse requirements and feasibility of perfect state transfer using the natural dynamics of spin chains and present an extensive investigation into the effects of a number of perturbations on the dynamics of these devices. This includes both fabrication defects and other sources of perturbations. We also present other potential uses of spin chains, including state storage, and introduce an original protocol for the generation of cluster state ladders using only a single linear spin chain.EThOS - Electronic Theses Online ServiceGBUnited Kingdo