Katherine Brown
University of Leeds
Using the qubus for quantum computing
The qubus is an ancilla based scheme of quantum computing. In this
particular case a continuous variable field is used to mediate
interactions between the qubits of the main system. Using such a scheme
it is possible to generate a maximally entangling gate between two
qubits and since we can perform local unitaries on the individual
qubits this scheme is universal for quantum computation. In this talk
we consider two systems that can be performed on the qubus; cluster
state generation and simulating the BCS Hamiltonian. Since these two
systems involve performing identical interactions on different qubits
we show that it is possible to get a significant reduction in the
number of operations needed to perform these systems by careful
rearrangement of the gates involved. We also discuss other systems
where a similar improvement may be found and show the limits of this
technique.