Key Laboratory of Quantum Structure and Quantum Control of Ministry of Education and Department of Physics, Hunan Normal University, Changsha 410081, China
Abstract This paper considers a generalized spin star system which can be
solved exactly, with the central spin-$\ddfrac{1}{2}$ system embedded
in an outer ring of $N$ spin-$\ddfrac{1}{2}$ particles(denoted as
spin bath). In this model, in addition to the central-outer
interaction, each pair of nearest neighbour of the bath interacts
within themselves. The general expressions of the eigenstates as well
as the eigenvalues of the model are derived with the use of the
symmetries of system. It analyses the quantum state transfer and the
dynamical behaviour of entanglement created during quantum
communication. It also analyses the efficiency of the configuration
regarded as quantum phase covariant clone or decoherence model. Some
interesting results are discovered concerning the properties of
quantum communication in this model.
Received: 19 April 2007
Revised: 22 June 2007
Published: 20 February 2008
