Abstract:
The task of constructing a quantum computer has many technical
challenges associated with it. One such example is transferring the
state of a quantum system between different
components of a quantum computer. A common approach to this problem
is the use of a quantum wire, i.e. a chain or network of coupled
quantum systems where the interactions are such that the quantum
state is transferred through the wireThe approach that is often taken
to the problem of perfect state transfer (PST) is to construct a
Hamiltonian and
show that this allows the state to be perfectly transferred. An
alternative approach has been proposed that enables a broad class of
Hamiltonians to be constructed. This approach
does not make any assumptions about the coupling or the topology of
the network. Instead, a class of Hamiltonians that lead to a
particular permutation are derived. This work was
developed for the task of transferring a single excitation between
two points in a network. We will show how one can use the formalism
outlined in to control quantum information in a more general manner.
For example, we may wish to transfer a state between several
different nodes within a network, at different times. This would
enable us to generalize the problem of PST to networks with a
nontrivial logical bus topology.
